11 - System pass
12 - RPM unable to reach upper test limit
13 - RPM unable to reach lower test limit
14 - Pip circuit failure
15 - PCM read only memory test failed
15 - PCM keep alive memory test failed
P0121 In-Range Operating Throttle Position Sensor circuit failure.
P0122 Throttle Position Sensor circuit Low Input.
P0123 Throttle Position Sensor circuit High Input.
P0125 Insufficient Coolant Temperature to enter Closed Loop.
P0126 Insufficient Coolant Temperature for Stable Operation.
16 - IDM signal not received
18 - SPOUT circuit open or spark angle word failure
18 - IDM circuit failure or SPOUT circuit grounded
21 - ECT out of self-test range
22 - BP sensor out of self-test range
22 - BP sensor or MAP out of range
23 - TP sensor out of self-test range
24 - ACT sensor out of self-test range
25 - Knock not sensed during dynamic test
26 - VAF/MAF out of self-test range
26 - TOT out of self-test range
26 - TOT sensor out of self-test range (E4OD)
28 - Loss of IDM, right side
29 - Insufficient input from vehicle speed sensor
31 - PFE, EVP or EVR circuit below minimum voltage
32 - EVP voltage below closed limit
33 - EGR valve opening not detected
34 - EVP voltage above closed limit
35 - PFE or EVP circuit above closed limit
41 - HEGO sensor circuit indicates system lean
41 - No HEGO switching detected
42 - HEGO sensor circuit indicates system rich
44 - Thermactor air system inoperative-right side
45 - Thermactor air upstream during self-test
45 - Coil 1, 2 or 3 failure
46 - Thermactor air not bypassed during self-test
47 - 4WD switch closed (E4OD)
48 - Loss of IDM, left side
49 - 1-2 shift error (E4OD)
51 - ECT/ACT reads -40°F or circuit open
52 - Power steering pressure switch circuit open
52 - Power steering pressure switch always open or closed
53 - TP circuit above maximum voltage
54 - ACT sensor circuit open
56 - VAF or MAF circuit above maximum voltage
56 - TOT reads -40°F or circuit open (E4OD)
59 - 2-3 shift error (E4OD)
61 - ECT reads 254°F or circuit grounded
63 - TP circuit below minimum voltage
64 - ACT sensor grounded or input reads 254°F
65 - Overdrive cancel switch open, no change seen (E4OD)
66 - MAF sensor input below minimum voltage
66 - TOT grounded or reads 290°F (E4OD)
67 - Neutral/drive switch open or A/C on
67 - Clutch switch circuit failure
67 - MLP sensor out of range or A/C on (E4OD)
69 - 3-4 shift error
72 - Insufficient MAF/MAP change during dynamic test
73 - Insufficient TP change during dynamic test
74 - Brake on/off switch failure or not actuated
77 - Operator error
79 - A/C on during self-test
79 - A/C or defrost on during self-test
81 - Air management 2 circuit failure
82 - Air management 1 circuit failure
84 - EGR vacuum solenoid circuit failure
85 - Canister purge solenoid circuit failure
86 - Shift solenoid circuit failure
87 - Fuel pump primary circuit failure
88 - Loss of dual plug input control
89 - Converter clutch solenoid circuit failure
91 - Shift solenoid 1 circuit failure (E4OD)
92 - Shift solenoid 2 circuit failure (E4OD)
93 - Coast clutch solenoid circuit failure (E4OD)
94 - Converter clutch solenoid circuit failure (E4OD)
95 - Fuel pump secondary circuit failure - PCM to ground
96 - Fuel pump secondary circuit failure - battery to PCM
97 - Overdrive cancel indicator light - circuit failure (E4OD)
98 - Electronic pressure control driver open in PCM (E4OD)
98 - Hard fault present
99 - Electronic pressure control circuit failure (E4OD)
111 - System pass
112 - ACT sensor circuit grounded or reads 254°F
113 - ACT sensor circuit open or reads -40°F
114 - ACT outside test limits during KOEO or KOER tests
116 - ECT outside test limits during KOEO or KOER tests
117 - ECT sensor circuit grounded
117 - ECT sensor circuit below minimum voltage or reads 254°F
118 - ECT sensor circuit open
118 - ECT sensor circuit below maximum voltage or reads -40°F
121 - Closed throttle voltage higher or tower than expected
122 - TP sensor circuit below minimum voltage
123 - TP sensor circuit below maximum voltage
126 - BP or MAP sensor higher or lower than expected
128 - MAP vacuum circuit failure
129 - Insufficient MAF or MAP change during dynamic responded test
144 - No HEGO switching detected
167 - Insufficient TP change during dynamic response test
171 - Fuel system at adaptive limit, HEGO unable to switch
172 - HEGO shows system always lean
173 - HEGO shows system always rich
174 - HEGO switching time is slow
179 - Fuel at lean adaptive limit at part throttle; system rich
181 - Fuel at rich adaptive limit at part throttle; system lean
182 - Fuel at lean adaptive limit at idle; system rich
183 - Fuel at rich adaptive limit at idle; system lean
211 - PIP circuit fault
212 - Loss of IDM input to PCM or SPOUT circuit grounded
213 - Spout circuit open
224 - Erratic IDM input to processor
225 - Knocked not sensed during dynamic response test
311 - Thermactor air system inoperative
312 - Thermactor air upstream during self-test
313 - Thermactor air not bypassed during self-test
327 - EVP or DPFE circuit below minimum voltage
328 - EGR closed voltage higher than expected
332 - Insufficient EGR flow detected
334 - EGR closed voltage higher than expected
337 - EVP or DPFE circuit above maximum voltage
411 - Cannot control rpm during KOER low rpm check
412 - Cannot control rpm during KOER high rpm check
452 - Insufficient input from vehicle speed sensor
511 - EEC processor ROM test failed
512 - EEC processor Keep Alive Memory test failed
513 - Failure in EEC processor internal voltage
519 - Power steering pressure switch circuit open
521 - Power steering pressure switch did not change state
525 - Vehicle in gear or A/C on during self-test
536 - Brake on/off circuit failure, switch not actuated during KOER test
538 - Insufficient RPM change during KOER dynamic response test
538 - Operator error
542 - Fuel pump secondary circuit failure: PCM to ground
543 - Fuel pump secondary circuit failure: Battery to PCM
552 - Air management 1 circuit failure
553 - Air management 2 circuit failure
556 - Fuel pump primary circuit failure
558 - EGR vacuum regulator circuit failure
565 - Canister purge circuit failure
569 - Canister purge 2 circuit failure
617 - 1-2 shift error (E4OD)
618 - 2-3 shift error (E4OD)
619 - 3-4 shift error (E4OD)
621 - Shift solenoid 1 circuit failure
622 - Shift solenoid 2 circuit failure
624 - EPC solenoid or driver circuit failure
625 - EPC driver open in PCM
626 - Coast clutch solenoid circuit failure (E4OD)
627 - Converter clutch solenoid circuit failure (E4OD)
628 - Converter clutch error (E4OD)
629 - Converter clutch control circuit failure
631 - Overdrive cancel indicator light circuit failure
632 - Overdrive cancel switch not changing states (E4OD)
633 - 4WD switch is closed
634 - MLP sensor voltage out of self-test range, A/C on
636 - TOT sensor voltage out of self-test range
637 - TOT sensor circuit above maximum voltage
638 - TOT sensor circuit below minimum voltage
654 - MLP sensor not in park position
998 - Hard fault present Definitions:
ACT = Air Charge Temperature Sensor
BP = See MAP
EEC = Electronic Engine Control System
ECT = Engine Coolant Temperature Sensor
EGR = Exhaust Gas Recirculation Valve
EVP = EGR Valve Position Sensor
HEGO = Heated Exhaust Gas Oxygen Sensor
KOEO = Key On Engine Off
KOER = Key On Engine Running
MAF = Mass Air Flow Sensor
MAP = Manifold Absolute Pressure Sensor
MLP = Manual Lever Position
PCM = Powertrain Control Module
SPOUT = Distributor Jumper to Allow Initial Timing
TP = Throttle Position Sensor Comments
1.Not all codes apply to all vehicles
2.Some codes have 2 listings, use the appropriate one This info was found at Chilton's "FORD Full Size Trucks 1987-96 Repair Manual" Here's another chart we found with some slight differences...
EEC-IV Diagnostic Codes, Rev. 1.1 2/25/93
11- (orc): No problems found in this portion of the test
12- (r): ECA could not increase idle speed above normal idle.
Suspect throttle body coking. KE1
13- (r): ECA could not lower idle speed.
Suspect Idle Bypass valve problems. KE15
14- (c): Intermittent PIP signal operation.
Suspect PIP sensor or TFI module, or grounding or
interference problems at the TFI module. Y1
15- (o): ECA ROM test failure- failure is internal to ECA.
(c) ECA KAM (Keep Alive RAM Memory) failure. Q10
18- (r*): Loss of TACH signal from TFI (Thick Film Integration- the module
on the side of the distributor) module to the ECA. There is an open in the SPOUT circuit. Suspect SPOUT connector. N1
19- (o): Failure of ECA voltage regulator. Replace ECA.
21- (or): ECT (Engine Coolant Temp) out of range. Coolant is less than 50degF for KOEO, or less than 180degF for KOER, or greater than 250degF for either. If coolant temp is in proper range, suspect ECT sensor (It won't be, for KOER tests on cars tha have a 160degF thermostat!) DE1, DE90
22- (orc*): MAP (Manifold Absolute Pressure, for speed-density cars) or
BP (Barometric Pressure, for mass-air cars) sensor signal out of range.
Suspect MAP or BP sensor and harness. DF1, DF90
23- (or): Closed throttle TP (Throttle Position) sensor voltage out of range. Suspect TP sensor. DH1
24- (or): ACT (Air Charge Temperature) sensor voltage out of range.
Suspect ACT sensor and harness. 1984-85 2.3 Turbo - Vane Air Flow voltage out of range. DA1
25- (r): 2.3 Turbo. Knock Sensor failure. DG1
26- (or): VAF (Vane Air Flow, 2.3L Turbo) or MAF (Mass Air Flow) signal out of range. Suspect sensor and harness. DK1
28- (or): 1986+ 2.3 Turbo. Vane Air Temperature out of range.
34- (r): 2.3 Turbo. EGR On/Off not working. KA1
41- (c): 2.3 Turbo. EGO read lean for more than 15 seconds while in closed loop. HA11
42- (c): 2.3 Turbo. EGO read rich for more than 15 seconds while in closed loop. HA8
51- (orc*): ECT voltage too high (coolant too cold, circa -40degF!).
Suspect ECT, harness. DE10, DE91
53- (orc*): TP sensor voltage too high (indicates WOT condition). DH3, DH90
54- (orc*): ACT (air Charge Temperature) sensor voltage too high. DA10, DA90
56- (orc*): MAF (VAF for 2.3 Turbo) sensor voltage too high. DK10, DK90
61- (orc*): ECT voltage too low- indicates coolant temp greater than 250degF. DE20, DE94
63- (orc*): TP sensor voltage too low. DH10, DH94
64- (orc*): ACT (1984-84 2.3 Turbo, VAT) sensor voltage too low, indicates intake air temp greater than 250degF. DA20, DA93
66- (rc*): MAF (2.3 Turbo, VAF) below minimum test voltage. DK20, DK93
67- (o): Clutch switch open, AC left on, transmission in gear. FA1
68- (oc): 1986+ 2.3 Turbo. VAT out of range.
73- (r): Insufficient goose during Dynamic Response test. Rerun test, goose it harder. 2.3 Turbo - Faulty Throttle Position sensor. DH20
74- No Brake Switch Actuation / Cruise Control Switch Actuation Detected
76- (r): 2.3L Turbo only. Insufficient VAF variation seen during Dynamic
Response test. DK30
77- (r): No goose detected durning Dynamic Respose test. Rerun test, goose it harder. M1
81- (o): 2.3 Turbo. Boost control circuit failure. KN1
82- (o): 2.3 Turbo. Check EDF signal to Integrated Controller for short to ground.
83- (o): 2.3L Turbo only. Check for EDF signal to Integrated Controller for open circuit.
84- (o): EVR solenoid circuit failure. 2.3 Turbo - Check for EGR solenoid open circuit.
85- (o): 2.3 Turbo with Automatic (T-Bird). Check for 3-4 shift solenoid open circuit.
87- (oc): FP relay circuit failure- suspect intertia switch, fusible link, FP relay. J1
98- (r): Hard fault present. The ECA is running in FMEM (Failure Effects Management Mode), so something is royally screwed up that the KOEO test should have told you about. Rerun KOEO and fix whatever you find there.
99- ECA hasn't learned yet |
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