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Home >> Ford >> 1988 >> Bronco II 4WD, Standard, M5OD-R1 >> Repair and Diagnosis >> Engine Performance >> System >> EEC-IV CEC System >> Quick Test >> Service Code Definitions
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Service Code Definitions

SERVICE CODE DEFINITIONS

Codes Definition
11 System "Passes" test procedure
12 Idle RPM not within specifications
13 Idle Speed Control (ISC) RPM too high
14 Erratic ignition signal from PIP
15 Power interrupted to Keep Alive Memory (KAM), Pin No. 1
16 Idle Speed Control (ISC) RPM too high or throttle pedal touched during KOER SELF-TEST
17 Idle Speed Control (ISC) RPM too low
18 Spark timing incorrect
19 Idle Speed Control (ISC) RPM too low
21 Engine Coolant Temperature (ECT) sensor/signal out of range
22 Manifold Absolute Pressure (MAP) sensor/signal out of range
23 Throttle Position Sensor (TPS) signal/out of range
24 Air Charge Temperature (ACT) sensor/signal out of range
25 Knock sensor signal not received by ECA
26 Mass Air Flow sensor (MAF) signal out of range
27 Vehicle Speed Sensor (VSS) signal not received (2.3L Turbo MPFI)
28 Ambient temperature less than 50°F (10°C)
29 Vehicle Speed Sensor (VSS) not functioning
31 Pressure Feedback EGR (PFE) circuit open
32 EGR Control solenoid (EGRC) or EGR Vent solenoid (EGRV) signal failure
33 EGR valve not operating or sticking
34 EGR Control solenoid (EGRC) or EGR Vent solenoid (EGRV) signal failure
35 RPM too low for EGR testing or Pressure Feedback EGR (PFE) circuit short
38 Idle Tracking Switch (ITS) sticking or open in signal circuit
39 Converter by-pass clutch not operating correctly
41 Heated Exhaust Gas Oxygen (HEGO) sensor, lean signal in closed loop. (On 5.0L MA SEFI, indicates RH sensor)
42 Heated Exhaust Gas Oxygen (HEGO) sensor signal rich in closed loop. Excessive fuel pressure or volume (On 5.0L MA SEFI, indicates RH sensor)
43 Heated Exhaust Gas Oxygen (HEGO) sensor signal lean during WOT test
44 Air management system (TAB/TAD solenoids)
45 Thermactor Air Diverter (TAD) system operation
46 Thermactor Air By-pass (TAB) system operation
47 Idle speed control (by-pass Air), low flow of unmetered air
48 Idle speed control (by-pass Air), high flow of unmetered air
51 Engine Coolant Temperature (ECT) sensor, signal circuit open
52 Power Steering Pressure Switch (PSPS) open/shorted, steering wheel not turned during KOER SELF-TEST
53 Throttle Position Sensor (TPS) signal circuit short
54 Air Charge Temperature (ACT) sensor circuit open
55 Key power check circuit open (CFI engines)
56 Vane Airflow (VAF) sensor or Mass Air Flow (MAF) sensor, shorted VREF to SIG circuit
57 Neutral Pressure Switch (NPS) failed in neutral
58 Vane Air Temperature (VAT) sensor circuit open
59 Transmission Hydraulic Switch (THS), 4/3 pressure switch, failed in open position
61 Engine Coolant Temp. (ECT) sensor, signal circuit short
62 Transmission Hydraulic Switch (THS) 4/3 pressure switch failed in closed position
63 Throttle Position Sensor (TPS) signal circuit open
64 Air Charge Temperature (ACT) sensor circuit short
65 Did not go to closed loop fuel control on HEGO switching. Faulty HEGO signal
66 Vane Airflow (VAF) sensor or Mass Air Flow (MAF) sensor, shorted SIG to SIG RTN circuit
67 Neutral Drive Switch (NDS), A/C Input, Neutral Pressure Switch (NPS) signal interrupted
68 Vane Air Temperature (VAT) sensor circuit short
69 Transmission Hydraulic Switch (THS) 3/2 pressure switch failed in closed position
71 Idle Tracking Switch (ITS) shorted to ground or stuck closed
72 Fault in VPWR circuit to EEC power relay
73 Throttle Position Sensor (TPS) did not rotate more than 25% during dynamic response test
74 Brake On/Off (BOO) switch always open or not applied during KOER SELF-TEST
75 Brake On/Off (BOO) switch always closed, or signal circuit shorted
76 Vane Airflow (VAF) sensor, no voltage signal increase during Dynamic Response Test
77 ECA request for Dynamic Response Test
78 Power supply circuit to EEC power relay interrupted
79 Neutral Drive Switch (NDS), A/C Input, Neutral Position Switch (NPS) signal interrupted
81 Open or shorted signal from turbo boost solenoid
82 Integrated Controller Relay Module (ICRM), electric fan processor signal shorted to ground or open
83 Integrated Controller Relay Module (ICRM), high speed electric fan processor signal shorted to ground or open
84 EGR Valve Regulator (EVR) resistance signal out of range
85 Fuel mixture made leaner (Adaptive Fuel) to accommodate canister purge function or excessive fuel pressure or volume
86 Fuel mixture made richer (Adaptive Fuel) due to low fuel pressure or low volume
87 Open in fuel pump circuit or VPWR circuit between EEC power relay and fuel pump relay
88 Integrated Controller Relay Module (ICRM), electric fan processor signal shorted to ground or open
89 Converter by-pass clutch solenoid always open or closed
91 Heated Exhaust Gas Oxygen (HEGO) sensor, lean signal in closed loop (on 5.0L MA SEFI, indicates LH sensor)
92 Heated Exhaust Gas Oxygen (HEGO) sensor signal rich in closed loop; excessive fuel pressure or volume (on 5.0L MA SEFI, indicates LH sensor)
93 Throttle linkage, DC motor idle speed control/idle tracking switch and Throttle Position Sensor (TPS) (1.9L & 2.5L CFI)
94 Air management system (TAB/TAD solenoids)
95 Inertia switch or fuel pump circuit shorted or open
96 No power to fuel pump relay
98 Vehicle did not pass KOEO SELF-TEST. Code 11 necessary to proceed with KOER test
99 ECA has not stored enough information to control idle speed