EEC-IV Diagnostic Codes 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 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"
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
This info was found at:http://www.corral.net/20anngt/