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Diagnostic Trouble Code (DTC) Definitions

WARNING: This page is about a different car, the 1999 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Front radio control unit may also be referred to as Audio Control Module (ACM). Speed control servo may also be referred to as Next Generation Speed Control (NGSC) servo. Air Suspension/Electronic Variable Orifice (EVO) steering module may also be referred to as Rear Air Suspension Module (RASM). Instrument cluster may also be referred to as Hybrid Electronic Cluster (HEC).
NOTE: For Powertrain Control Module (PCM) DTC identification and repair see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
AIR SUSPENSION/ELECTRONIC VARIABLE ORIFICE STEERING MODULE DTC INDEX

DTC Description Perform Test
B1317 Battery Voltage High (1)
B1318 Battery Voltage Low (1)
B1342 ECU Defective (2)
C1441 Steering Sensor Channel A Circuit Failure (3)
C1442 Steering Sensor Channel B Circuit Failure (3)
C1722 Air Suspension Height Sensor Power Circuit Short To Voltage (1)
C1723 Air Suspension Height Sensor Power Circuit Short To Ground (1)
C1760 Air Suspension Rear Height Sensor High Signal Circuit Failure (1)
C1763 Air Suspension Rear Height Sensor High Signal Circuit Short To Ground (1)
C1765 Air Suspension Rear Height Sensor Low Signal Circuit Failure (1)
C1768 Air Suspension Rear Height Sensor Low Signal Circuit Short To Ground (1)
C1770 Air Suspension Vent Solenoid Output Circuit Failure (1)
C1773 Air Suspension Vent Solenoid Output Circuit Short To Ground (1)
C1790 Air Suspension Left Rear Air Spring Solenoid Output Circuit Failure (1)
C1793 Air Suspension Left Rear Air Spring Solenoid Output Circuit Short To Ground (1)
C1795 Air Suspension Right Rear Air Spring Solenoid Output Circuit Failure (1)
C1798 Air Suspension Right Rear Air Spring Solenoid Output Circuit Short To Ground (1)
C1813 Air Suspension Vent Request Exceeded Maximum Time (1)
C1818 Air Suspension Air Compressor Request Exceeded Maximum Time (1)
C1830 Air Compressor Relay Circuit Failure (1)
C1832 Air Compressor Relay Circuit Short To Voltage (1)
C1840 Air Suspension Switch Circuit Failure (1)
C1842 Air Suspension Switch Circuit Short To Voltage (1)
C1897 Steering VAPS Circuit Loop Failure (3)
U1041 SCP Invalid/Missing Data For Vehicle Speed (4)
(1) Repair electronic suspension concern. See appropriate ELECTRONIC article in SUSPENSION.
(2) Using NGS tester, retrieve and document all continuous DTCs. Perform air suspension/electronic variable orifice steering module self-test. If DTC B1342 is retrieved again, replace air suspension/electronic variable orifice steering module.
(3) Repair electronic steering concern. See appropriate ELECTRONIC article in STEERING.
(4) Cause By Anti-Lock Brake System (ABS) module. Using NGS tester, perform ABS self-test and repair anti-lock brake system concern. See appropriate ANTI-LOCK article in BRAKES.
ANTI-LOCK BRAKE SYSTEM MODULE DTC INDEX

DTC Description Perform Test
B1342 ECU Defective (1)
B1485 Brake Pedal Input Circuit Shorted To Voltage (2)
B1676 Battery Voltage Out Of Range (2)
C1095 ABS Hydraulic Pump Motor Circuit Failure (2)
C1145 Right Front ABS Sensor Input Circuit Failure (2)
C1155 Left Front ABS Sensor Input Circuit Failure (2)
C1165 Right Rear ABS Sensor Input Circuit Failure (2)
C1175 Left Rear ABS Sensor Input Circuit Failure (2)
C1233 Left Front ABS Sensor Input Signal Missing (2)
C1234 Right Front ABS Sensor Input Signal Missing (2)
C1235 Right Rear ABS Sensor Input Signal Missing (2)
C1236 Left Rear ABS Sensor Input Signal Missing (2)
U1009 SCP Invalid/Missing Data For Engine Torque (3)
U1027 SCP Invalid/Missing Data For Engine RPM (3)
U1041 SCP Invalid/Missing Data For Vehicle Speed (4)
U1043 SCP Invalid/Missing Data For Traction Control (5)
U1059 SCP Invalid/Missing Data For Transmission Range (PRNDL) (3)
U1123 SCP Invalid/Missing Data For Odometer (6)
(1) Using NGS tester, retrieve and document all continuous DTCs. Perform ABS self-test. If DTC B1342 is retrieved again, replace ABS module.
(2) Repair anti-lock brake system concern. See appropriate ANTI-LOCK article in BRAKES.
(3) Cause by Powertrain Control Module (PCM). Using NGS tester, perform PCM self-test and repair powertrain control concern. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
(4) Caused by instrument cluster, Driver's Door Module (DDM), Lighting Control Module (LCM), Restraint Control Module (RCM) and/or speed control servo control module. Using NGS tester, perform self-test on all these modules.
(5) Cause by instrument cluster. Using NGS tester, perform instrument cluster self-test.
(6) Caused by instrument cluster and/or air suspension/electronic variable orifice steering module. Using NGS tester, perform instrument cluster and air suspension/electronic variable orifice steering module self-test.
DRIVER'S DOOR MODULE DTC INDEX

DTC Description Perform Test
B1322 Driver's Door Ajar Circuit Failure (1)
B1342 ECU Defective (2)
B1396 Power Door Lock Circuit Short To Voltage (3)
B1397 Power Door Unlock Circuit Short To Voltage (3)
B1402 Driver's Door Window Switch Down Circuit Open (4)
B1529 Memory Set Switch Circuit Short To Voltage (5)
B1533 Memory "1" Switch Circuit Short To Voltage (5)
B1537 Memory "2" Switch Short To Voltage (5)
B1545 Power Seat Switch Short To Voltage (6)
B1549 Power Window Switch Short To Voltage (4)
B1553 Trunk Release Switch Circuit Short To Voltage (3)
B1566 Passenger's And/Or Rear Door Ajar Circuits Short To Ground (1)
B2338 Mirror Switch Assembly Circuit Short To Voltage (7)
B2368 Memory LED Output Short To Voltage (5)
B2373 LED "1" Circuit Short To Voltage (8)
B2425 Remote Keyless Entry Out Of Synchronization (9)
C1920 LED "1" Circuit Failure (5)
U1041 SCP Invalid/Missing Data For Vehicle Speed (10)
U1059 SCP Invalid/Missing Data For Transmission Range (PRNDL) (11)
U1089 SCP Invalid/Missing Data For Suspension (12)
U1135 SCP Invalid/Missing Data For Ignition Switch (13)
U1181 SCP Invalid/Missing Data For Personalization (Memory) Features (14)
U1199 SCP Invalid/Missing Data For External Access (Doors) (15)
U1222 SCP Invalid/Missing Data For Interior Lights (15)
U1262 SCP Bus Communication Fault (16)
(1) Perform TEST Q: COURTESY LIGHTS STAY ON CONTINUOUSLY under SYSTEM TESTS in AUTOLAMP SYSTEMS article.
(2) Using NGS tester, retrieve and document all continuous DTCs. Perform DDM self-test. If DTC B1342 is retrieved again, replace DDM.
(3) Repair appropriate keyless entry system circuit. See appropriate wiring diagram in REMOTE KEYLESS ENTRY SYSTEMS article.
(4) Perform TEST B: SINGLE WINDOW INOPERATIVE under SYSTEM TESTS in POWER WINDOWS - CONTINENTAL article.
(5) Perform TEST D: MIRROR OPERATES IN ONE SECOND INTERVALS under SYSTEM TESTS in POWER MIRRORS - TOWN CAR article.
(6) Perform TEST C: DRIVER'S SEAT COMPLETELY INOPERATIVE (WITH MEMORY) under SYSTEM TESTS in POWER SEATS - TOWN CAR article.
(7) Perform TEST C: SINGLE MIRROR INOPERATIVE under SYSTEM TESTS in POWER MIRRORS - TOWN CAR article.
(8) Perform TEST G: MEMORY MIRRORS INOPERATIVE under SYSTEM TESTS in POWER MIRRORS - TOWN CAR article.
(9) Program transmitter. See TRANSMITTER under PROGRAMMING in PASSIVE ANTI-THEFT SYSTEMS - TOWN CAR article.
(10) Caused by Anti-Lock Brake System (ABS) module. Using NGS tester, perform ABS self-test and repair anti-lock brake system concern. See appropriate ANTI-LOCK article in BRAKES.
(11) Caused by Powertrain Control Module (PCM). Using NGS tester, perform PCM self-test and repair powertrain control concern. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
(12) Caused by air suspension/electronic variable orifice steering module. Using NGS tester, perform air suspension/electronic variable orifice steering module self-test and repair electronic suspension concern. See appropriate ELECTRONIC article in SUSPENSION.
(13) Caused by Lighting Control Module (LCM). Using NGS tester, perform LCM self-test and repair steering column switch concern. See SELF-DIAGNOSTIC SYSTEM in STEERING COLUMN SWITCHES - TOWN CAR article.
(14) Cause by Driver's Door Module (DDM). Using NGS tester, perform DDM self-test.
(15) Caused by Lighting Control Module (LCM). Using NGS tester, perform LCM self-test.
(16) Service all other DTCs first. After all other DTC concerns have been repaired, perform TEST M: NO MODULE/NETWORK COMMUNICATION - SCP BUS LINK  under SYSTEM TESTS.
DRIVER'S SEAT MODULE DTC INDEX

DTC Description Perform Test
B1342 ECU Defective (1)
B1663 Driver's Seat Front Up/Down Circuit Failure (2)
B1664 Driver's Seat Rear Up/Down Circuit Failure (2)
B1665 Driver's Seat Forward/Backward Circuit Failure (2)
B1666 Driver's Seat Recline Circuit Failure (2)
B1667 Driver's Mirror Up/Down Circuit Failure (3)
B1668 Driver's Mirror Right/Left Circuit Failure (3)
B1669 Passenger's Mirror Up/Down Circuit Failure (3)
B1670 Passenger's Mirror Right/Left Circuit Failure (3)
B1676 Battery Voltage Out Of Range (4)
B1950 Driver's Seat Rear Up/Down Potentiometer - Circuit Failure (5)
B1953 Driver's Seat Rear Up/Down Potentiometer - Short to Ground (5)
B1954 Driver's Seat Front Up/Down Potentiometer - Circuit Failure (5)
B1957 Driver's Seat Front Up/Down Potentiometer - Short to Ground (5)
B1958 Driver's Seat Recline Potentiometer - Circuit Failure (5)
B1961 Driver's Seat Recline Potentiometer - Short To Ground (5)
B1962 Driver's Seat Horizontal Potentiometer - Circuit Failure (5)
B1965 Driver's Seat Horizontal Potentiometer - Short To Ground (5)
B2312 Passenger's Mirror Right/Left Potentiometer - Circuit Failure (6)
B2315 Passenger's Mirror Right/Left Potentiometer - Short To Ground (6)
B2316 Passenger's Mirror Up/Down Potentiometer - Circuit Failure (6)
B2319 Passenger's Mirror Up/Down Potentiometer - Short To Ground (6)
B2320 Driver's Mirror Right/Left Potentiometer - Circuit Failure (6)
B2323 Driver's Mirror Right/Left Potentiometer - Shirt To Ground (6)
B2324 Driver's Mirror Up/Down Potentiometer - Circuit Failure (6)
B2327 Driver's Mirror Up/Down Potentiometer - Short To Ground (6)
U1059 SCP Invalid/Missing Data For Transmission Range (PRNDL) (7)
U1135 SCP Invalid/Missing Data For Ignition Switch (8)
U1180 SCP Invalid/Missing Data For Memory Feature (9)
U1181 SCP Invalid/Missing Data For Memory Feature (9)
U1194 SCP Invalid/Missing Data For Mirrors (9)
U1200 SCP Invalid/Missing Data For Seat Motion/Control (10)
U1262 SCP Bus Communication Fault (11)
(1) Using NGS tester, retrieve and document all continuous DTCs. Perform Driver's Seat Module (DSM) self-test. If DTC B1342 is retrieved again, replace DSM.
(2) Perform TEST C: DRIVER'S SEAT COMPLETELY INOPERATIVE (WITH MEMORY) under SYSTEM TESTS in POWER SEATS - TOWN CAR article.
(3) Perform TEST C: SINGLE MIRROR INOPERATIVE under SYSTEM TESTS in POWER MIRRORS - TOWN CAR article.
(4) Perform TEST P: BATTERY VOLTAGE OUT OF RANGE (DTC B1676) under SYSTEM TESTS in POWER SEATS - TOWN CAR article.
(5) Perform TEST E: SEAT MOTORS OPERATE IN ONE SECOND INTERVALS under SYSTEM TESTS in POWER SEATS - TOWN CAR article.
(6) Perform TEST D: MIRROR OPERATES IN ONE SECOND INTERVALS under SYSTEM TESTS in POWER MIRRORS - TOWN CAR article.
(7) Caused by Powertrain Control Module (PCM). Using NGS tester, perform PCM self-test and repair powertrain control concern. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE in appropriate lemon-25® manual.
(8) Caused by Lighting Control Module (LCM). Using NGS tester, perform LCM self-test and repair steering column switch concern. See SELF-DIAGNOSTIC SYSTEM in STEERING COLUMN SWITCHES - TOWN CAR article.
(9) Caused by Driver's Door Module (DDM). Using NGS tester, perform DDM self-test and repair power mirror system concern. See SELF-DIAGNOSTIC SYSTEM in POWER MIRRORS - TOWN CAR article.
(10) Caused by Driver's Door Module (DDM). Using NGS tester, perform DDM self-test and repair power seat system concern. See SELF-DIAGNOSTIC SYSTEM in POWER SEATS - TOWN CAR article.
(11) Service all other DTCs first. After all other DTC concerns have been repaired, perform TEST M: NO MODULE/NETWORK COMMUNICATION - SCP BUS LINK  under SYSTEM TESTS.
ELECTRONIC AUTOMATIC TEMPERATURE CONTROL MODULE DTC INDEX

DTC Description Perform Test
B1249 Blend Door Short (1)
B1251 A/C In-Car Temperature Sensor Open Circuit (1)
B1253 A/C In-Car Temperature Sensor Short To Ground (1)
B1255 A/C Ambient Temperature Sensor Open Circuit (1)
B1257 A/C Ambient Temperature Sensor Short To Ground (1)
B1261 A/C Solar Radiation Sensor Circuit Short To Ground (1)
B2416 Recirculated Air Door Circuit Failure (1)
U1041 SCP Invalid/Missing Data For Vehicle Speed (2)
U1073 SCP Invalid/Missing Data For Engine Coolant (2)
U1222 SCP Invalid/Missing Data For Interior Lights (3)
U1235 SCP Invalid/Missing Data For Displays (4)
(1) Repair climate control concern. See appropriate AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING.
(2) Caused by Powertrain Control Module (PCM). Using NGS tester, perform PCM self-test and repair powertrain control concern. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
(3) Cause by Lighting Control Module (LCM). Using NGS tester, perform LCM self-test and repair interior lighting concern. See SELF-DIAGNOSTIC SYSTEM in AUTOLAMP SYSTEMS - TOWN CAR article.
(4) Caused by instrument cluster module. Using NGS tester, perform instrument cluster self-test and repair instrument cluster concern. See SELF-DIAGNOSTIC SYSTEM in INSTRUMENT PANELS - TOWN CAR article.
FRONT RADIO CONTROL UNIT DTC INDEX

DTC Description Perform Test
B1342 ECU Defective (1)
B2401 Audio Tape Deck Mechanical Fault (2)
B2402 Audio CD/DJ Thermal Shutdown (3)
B2403 Audio CD/DJ Internal Fault (3)
B2404 Audio Steering Wheel Switch Circuit Failure (3)
B2405 Audio Single-Disc CD Player Thermal Shutdown Fault (3)
B2406 Audio Single-Disc CD Player Internal Fault (3)
U2003 Audio CD/DJ Is Not Responding (3)
U2005 Audio Rear Integrated Control Panel Unit Is Not Responding (5)
U2008 Audio Phone Is Not Responding (4)
U2014 Audio Subwoofer Unit Is Not Responding (3)
(1) Using NGS tester, retrieve and document all continuous DTCs. Perform front radio control unit self-test. If DTC B1342 is retrieved again, replace front radio control unit.
(2) Remove audio tape. Using NGS tester, clear DTCs. Perform front radio control unit self-test. If B2401 is retrieved, repair or replace front radio control unit.
(3) Repair audio system concern.
(4) Repair cellular phone system concern.
(5) This DTC is retrieved if vehicle is not equipped with Rear Audio Control Panel (RACP) or RACP is disconnected or inoperative.
INSTRUMENT CLUSTER DTC INDEX

DTC Description Perform Test
B1201 Fuel Sender Circuit Failure (1)
B1204 Fuel Sender Short To Ground (1)
B1205 Instrument Cluster Switch 1 Assembly Circuit Failure (Open Or Short To Voltage) (2)
B1208 Instrument Cluster Switch 1 Assembly Circuit Short To Ground (2)
B1213 Number Of Programmed Ignition Keys Below Minimum (3)(4)
B1232/2103 Antenna Not Connected/Defective Transceiver (5)
B1317 Battery Voltage High (Greater Than 19 Volts) (6)
B1318 Battery Voltage Low (Less Than 9 Volts) (6)
B1342 ECU Defective (7)
B1600 PATS Ignition Key Transponder Signal Not Received (Damaged Key Or Non-PATS Key) (8)
B1601 PATS Received Incorrect Key-Code From Ignition Key Transponder (9)
B1602 PATS Received Invalid Key Code Format From Transponder (10)
B1681 PATS Transceiver Signal Is Not Received (11)
B2139 PATS Data Mismatch (12)
B2141 NVM Configuration Failure (13)
B2143 NVM Memory Failure (14)
U1147 Invalid/Missing Data For Vehicle Security (15)
U1262 SCP Bus Communication Fault (16)
U2013 No Response From Compass Module (17)
(1) Perform TEST B: FUEL GAUGE INACCURATE under SYSTEM TESTS in INSTRUMENT PANELS - TOWN CAR article.
(2) Perform TEST AA: MESSAGE CENTER SWITCH NOT OPERATING PROPERLY under SYSTEM TESTS in INSTRUMENT PANELS - TOWN CAR article.
(3) If DTCs B1232, B1600, B1601, B1602 OR B1681 are also present, service these DTCs frist then recheck codes.
(4) Perform DTC B1213: ANTI-THEFT NUMBER OF PROGRAMED KEYS IS BELOW MINIMUM under DIAGNOSTIC TESTS in PASSIVE ANTI-THEFT SYSTEMS - TOWN CAR article.
(5) Perform DTC B1232/2103: DEFECTIVE TRANSCEIVER under DIAGNOSTIC TESTS in PASSIVE ANTI-THEFT SYSTEMS - TOWN CAR article.
(6) Check charging system. See appropriate GENERATORS article in STARTING & CHARGING SYSTEMS. If charging system is okay, check power and ground circuits to instrument cluster. See appropriate wiring diagram in POWER DISTRIBUTION article in WIRING DIAGRAMS.
(7) Using NGS tester, retrieve and record all continuous DTCs. Perform instrument cluster self-test. If DTC B1342 still exists, replace instrument cluster.
(8) Perform DTC B1600: PATS IGNITION KEY TRANSPONDER SIGNAL NOT RECEIVED under DIAGNOSTIC TESTS in PASSIVE ANTI-THEFT SYSTEMS - TOWN CAR article.
(9) Perform DTC B1601: PATS RECEIVED INCORRECT KEY CODE FROM IGNITION KEY TRANSPONDER under DIAGNOSTIC TESTS in PASSIVE ANTI-THEFT SYSTEMS - TOWN CAR article.
(10) Perform DTC B1602: PATS RECEIVED INVALID KEY CODE FORMAT FROM IGNITION KEY TRANSPONDER under DIAGNOSTIC TESTS in PASSIVE ANTI-THEFT SYSTEMS - TOWN CAR article.
(11) Perform DTC B1681: PATS TRANSCEIVER SIGNAL IS NOT RECEIVED under DIAGNOSTIC TESTS in PASSIVE ANTI-THEFT SYSTEMS - TOWN CAR article.
(12) Perform DTC B2139: PATS DATA MISMATCH under DIAGNOSTIC TESTS in PASSIVE ANTI-THEFT SYSTEMS - TOWN CAR article.
(13) Perform DTC B2141: NVM CONFIGURATION FAILURE under DIAGNOSTIC TESTS in PASSIVE ANTI-THEFT SYSTEMS - TOWN CAR article.
(14) Perform TEST V: ODOMETER INOPERATIVE under SYSTEM TESTS in INSTRUMENT PANELS - TOWN CAR article.
(15) Perform DTC U1147: INVALID OR MISSING DATA FOR VEHICLE SECURITY under DIAGNOSTIC TESTS in PASSIVE ANTI-THEFT SYSTEMS - TOWN CAR article.
(16) Service all other DTCs first. After all other DTC concerns have been repaired, perform TEST M: NO MODULE/NETWORK COMMUNICATION - SCP BUS LINK  under SYSTEM TESTS.
(17) Repair compass module circuits and/or replace compass module as necessary. See WIRING DIAGRAMS in INSTRUMENT PANELS - TOWN CAR article.
LIGHTING CONTROL MODULE DTC INDEX

DTC Description Perform Test
B1312 Headlight Input Short To Battery Voltage (1)
B1334 Trunk Lid Ajar Rear Door Circuit Short To Ground (2)
B1340 ECS Tone Request Short To Ground (3)
B1342 ECU Defective (4)
B1352 Ignition Key-In Circuit Failure (5)
B1359 Ignition RUN/ACC Input Circuit Failure (6)
B1462 Seat Belt Switch Circuit Failure (7)
B1485 Brake Pedal Input Circuit Short To Voltage (8)
B1555 Ignition RUN/START Circuit Failure (9)
B1569 High Beam Short To Battery Voltage (10)
B1577 Parking Lamp Input Short To Voltage (11)
B1581 Panel Dim Increase Input Circuit Short To Voltage (12)
B1585 Panel Dim Decrease Input Short To Voltage (12)
B1676 Battery Voltage Out Of Range (13)
B1687 Dome Light Input Short To Voltage (14)
B1689 Autolamp Delay Input Circuit Failure (15)
B1691 Autolamp Delay Input Circuit Short To Voltage (15)
B1695 Autolamp ON/OFF Short To Voltage (15)
B1873 Turn Signal/Hazard Power Feed Short To Ground (16)
U1041 SCP Invalid/Missing Data For Vehicle Speed (17)
U1059 SCP Invalid/Missing Data For Transmission Range (PRNDL) (18)
U1197 SCP Invalid/Missing Data For Door Locks (19)
U1199 SCP Invalid/Missing Data For External Access (Doors) (19)
(1) Perform TEST D: LOW BEAMS ARE ON CONTINUOUSLY (DAYTIME RUNNING LIGHTS ARE DISABLED) under SYSTEM TESTS in AUTOLAMP SYSTEMS - TOWN CAR article.
(2) See appropriate wiring diagram in REMOTE KEYLESS ENTRY SYSTEMS article.
(3) Repair short to ground in Electronic Crash Sensor (ECS) circuit. See DIAGNOSIS & TESTING in lemon-25® AIR BAG SERVICE & REPAIR MANUAL, DOMESTIC & IMPORTED MODELS.
(4) Using NGS tester, retrieve and document all continuous DTCs. Perform LCM self-test. If DTC B1342 is retrieved again, replace LCM.
(5) Perform TEST P: COURTESY LIGHTS INOPERATIVE under SYSTEM TESTS in AUTOLAMP SYSTEMS - TOWN CAR article.
(6) Perform TEST G: IGNITION RUN/ACC CIRCUIT FAILURE (DTC 1359) under SYSTEM TESTS in STEERING COLUMN SWITCHES - TOWN CAR article.
(7) Perform TEST N: NO COMMUNICATION WITH DRIVER'S DOOR MODULE under SYSTEM TESTS in AUTOLAMP SYSTEMS - TOWN CAR article.
(8) Perform TEST G: STOPLIGHTS INOPERATIVE under SYSTEM TESTS in AUTOLAMP SYSTEMS - TOWN CAR article.
(9) Perform TEST H: IGNITION RUN/START CIRCUIT FAILURE (DTC 1555) under SYSTEM TESTS in STEERING COLUMN SWITCHES - TOWN CAR article.
(10) Perform TEST C: HIGH BEAMS INOPERATIVE under SYSTEM TESTS in AUTOLAMP SYSTEMS - TOWN CAR article.
(11) Perform TEST M: PARKING, TAIL OR LICENSE LIGHTS ON CONTINUOUSLY under SYSTEM TESTS in AUTOLAMP SYSTEMS - TOWN CAR article.
(12) Perform TEST AJ: DASH DIMMING CONTROL INOPERATIVE under SYSTEM TESTS in INSTRUMENT PANELS - TOWN CAR article.
(13) Check charging system. See appropriate GENERATORS article in STARTING & CHARGING SYSTEMS. If charging system is okay, check power and ground circuits to LCM. See appropriate wiring diagram in POWER DISTRIBUTION article in WIRING DIAGRAMS.
(14) Perform TEST Q: COURTESY LIGHTS STAY ON CONTINUOUSLY under SYSTEM TESTS in AUTOLAMP SYSTEMS - TOWN CAR article.
(15) Perform TEST F: AUTOLAMP SYSTEM IS INOPERATIVE under SYSTEM TESTS in AUTOLAMP SYSTEMS - TOWN CAR article.
(16) Perform TEST H: TURN SIGNAL & HAZARD LIGHTS ARE INOPERATIVE under SYSTEM TESTS in AUTOLAMP SYSTEMS - TOWN CAR article.
(17) Caused by Anti-Lock Brake System (ABS) module. Using NGS tester, perform ABS self-test and repair anti-lock brake system concern. See appropriate ANTI-LOCK article in BRAKES in appropriate lemon-25® manual.
(18) Caused by Powertrain Control Module (PCM). Using NGS tester, perform PCM self-test and repair powertrain control concern. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE in appropriate lemon-25® manual.
(19) Caused by Driver's Door Module (DDM). Using NGS tester, perform DDM self-test.
RESTRAINT CONTROL MODULE DTC INDEX

DTC (1) Description Perform Test
B1342 ECU Defective (2)
B1231 RCM Internal Fault (3)
B1921 RCM Crash Data Memory Full (3)
C1414 Incorrect Vehicle Identification Code (3)
B1887 Driver's Air Bag Circuit Shorted To Ground (3)
B1916 Driver's Air Bag Circuit Shorted To Voltage (3)
B1888 Passenger's Air Bag Circuit Shorted To Ground (3)
B1925 Passenger's Air Bag Circuit Shorted To Voltage (3)
B1932 Driver's Air Bag Circuit Resistance High (3)
B1933 Passenger's Air Bag Circuit Resistance High (3)
B1934 Driver's Air Bag Circuit Resistance Low (3)
B1935 Passenger's Air Bag Circuit Resistance Low (3)
B1901 External Crash Sensor Shorted To Ground (3)
B1941 External Crash Sensor Open Circuit Shorted To Voltage (3)
B2444 Driver's Side Crash Sensor Internal Fault (3)
B2445 Passenger's Side Crash Sensor Internal Fault (3)
B2441 Driver's Side Crash Sensor Mounting Fault (3)
B2440 Passenger's Side Crash Sensor Mounting Fault (3)
U2017 Driver's Side Crash Sensor Communication Fault (3)
U2018 Passenger's Side Crash Sensor Communication Fault (3)
B1993 Driver's Side Air Bag Circuit Shorted To Ground (3)
B1992 Driver's Side Air Bag Circuit Shorted To Voltage (3)
B1994 Driver's Side Air Bag Circuit Resistance High (3)
B1995 Driver's Side Air Bag Circuit Resistance Low (3)
B1997 Passenger's Side Air Bag Circuit Shorted To Ground (3)
B1996 Passenger's Side Air Bag Circuit Shorted To Voltage (3)
B1998 Passenger's Side Air Bag Circuit Resistance High (3)
B1999 Passenger's Side Air Bag Circuit Resistance Low (3)
B1892 Air Bag Tone Warning Indicator Circuit Shorted To Ground Or Open (3)
B1891 Air Bag Tone Warning Indicator Circuit Shorted To Voltage (3)
B1869 Air Bag Indicator Inoperative (3)
B1870 Air Bag Indicator Shorted To Voltage (3)
(1) DTCs are listed in order of importance. Repair DTCs in order listed.
(2) Using NGS tester, retrieve and document all continuous DTCs. Perform Restraint Control Module (RCM) self-test. If DTC B1342 is retrieved again, replace RCM.
(3) Repair supplemental restraint system concern. See DIAGNOSIS & TESTING article in appropriate lemon-25® AIR BAG SERVICE & REPAIR MANUAL, DOMESTIC & IMPORTED MODELS.
SPEED CONTROL SERVO DTC INDEX

DTC Description Perform Test
B1318 Battery Voltage Low (1)
B1342 ECU Defective (2)
C1109 Throttle Position Did Not Return To Idle After Self-Test (3)
C1126 Speed Control Switch Stuck For 2 Minutes Or Longer (4)
C1127 Deactivator Switch Circuit Failure (5)
C1179 Speed Control Cable Slack Failure (6)
U1027 SCP Invalid/Missing Data For Engine RPM (7)
U1041 SCP Invalid/Missing Data For Vehicle Speed (8)
U1051 SCP Invalid/Missing Data For Brakes (9)
U1059 SCP Invalid/Missing Data For Transmission Range (PRNDL) (7)
(1) Perform TEST C: BATTERY VOLTAGE LOW (DTC B1318) under SYSTEM TESTS in CRUISE CONTROL SYSTEMS - TOWN CAR article.
(2) Using NGS tester, retrieve and document all continuous DTCs. Perform air suspension/electronic variable orifice steering module self-test. If DTC B1342 is retrieved again, replace air suspension/electronic variable orifice steering module.
(3) Perform TEST D: THROTTLE POSITION DID NOT RETURN TO IDLE AFTER SELF-TEST (DTC C1109) under SYSTEM TESTS in CRUISE CONTROL SYSTEMS - TOWN CAR article.
(4) Perform TEST E: SPEED CONTROL SWITCH STUCK FOR 2 MINUTES OR LONGER (DTC C1126) under SYSTEM TESTS in CRUISE CONTROL SYSTEMS - TOWN CAR article.
(5) Perform TEST F: DEACTIVATOR SWITCH CIRCUIT FAILURE (DTC C1127) under SYSTEM TESTS in CRUISE CONTROL SYSTEMS - TOWN CAR article.
(6) Perform TEST G: SPEED CONTROL SERVO/ACTUATOR CABLE SLACK FAILURE (DTC C1179) under SYSTEM TESTS in CRUISE CONTROL SYSTEMS - TOWN CAR article.
(7) Cause by Powertrain Control Module (PCM). Using NGS tester, perform PCM self-test and repair powertrain control concern. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE in appropriate lemon-25® manual.
(8) Cause by Anti-Lock Brake System (ABS) module. Using NGS tester, perform ABS self-test and repair anti-lock brake system concern. See appropriate ANTI-LOCK article in BRAKES in appropriate lemon-25® manual.
(9) Caused by Lighting Control Module (LCM). Using NGS tester, perform LCM self-test.
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