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Trouble Code Diagnostic Hints

NOTE: To determine a common cause for a trouble code to be set, see TROUBLE CODE DIAGNOSTIC HINTS  table.
TROUBLE CODE DIAGNOSTIC HINTS (1)

Trouble Code Diagnostic Hints
12 No "G", "G1", "G2" or "NE" Ignition Signal To ECM Within 2 Seconds After Engine Is Cranked, No "G" Ignition Signal To ECM For 3 Seconds With Engine Speed Of 600-4000 RPM Open In "G-" Circuit
13 No "NE" Ignition Signal To ECM When Engine Speed Is Greater Than Approximately 1000 RPM, No "G" Ignition Signal To ECM When "NE" Signal Is Input 4 Times With Engine Speed Of 600-4000 RPM
14 No "IG" Or "IGF" Ignition Signal To ECM From Ignitor Several Times In Succession
16 Fault In Transmission/Transaxle ECU Or ECM
21 Defective O2 Sensor, Open Or Short Circuit In O2 Sensor Signal
22 Open Or Short Circuit In Engine Coolant Temp. Sensor Signal
24 Open Or Short Circuit In Intake Air Temp. Sensor Signal
25 Lean Signal Sent By O2 Sensor For Several Seconds
26 Rich Signal Sent By O2 Sensor For Several Seconds
27 Open Or Short Circuit In Sub-O2 Sensor Signal
28 Defective O2 Sensor, Open Or Short Circuit In O2 Sensor Signal
31 Open Or Short Circuit In Airflow Meter Or MAP Sensor Signal
32 Open Or Short Circuit Between Airflow Meter Terminals
41 Open Or Short Circuit In Throttle Position Sensor Signal
42 No Signal From Vehicle Speed Sensor For Several Seconds
43 No "STA" Signal To ECM Until Engine Reaches 800 RPM With Engine Cranking
47 Open Or Short Circuit In Sub-Throttle Position Sensor Signal
51 (2) Problem In One Of 3 Circuits Monitored By ECM
52 Open Or Short Circuit In Knock Sensor Signal
53 Knock Control In ECM Is Faulty
55 Open Or Short Circuit In Knock Sensor Signal
71 EGR Gas Temp. Less Than Predetermined Level During EGR Control
78 Open Or Short Circuit In Fuel Pump Control Circuit Or Fuel Pump Electronic Control Unit (ECU)
81 Open In ECT1 Circuit Between ECM & Trans. Control Module (TCM) For At Least 2 Seconds
83 Open In ESA1 Circuit Between ECM & Trans. Control Module (TCM) For 1/2 Second After Engine Idles At Least 1/2 Second
84 Open In ESA2 Circuit Between ECM & Trans. Control Module (TCM) For 1/2 Second After Engine Idles At Least 1/2 Second
85 Open In ESA3 Circuit Between ECM & Trans. Control Module (TCM) For 1/2 Second After Engine Idles At Least 1/2 Second
(1) Listed are possible areas causing trouble codes. Not all trouble codes are used on all models.
(2) Throttle position sensor, Park/Neutral switch and A/C Signal circuits are monitored.