1990 Ford Bronco II RWD, Standard, M5OD-R1FACTORY OEM SERVICE PROCEDURE

2.3L VIN [A]

CODE DEFINITION

Code Condition (1) Definition
11 orc System pass
12 r Cannot control RPM during Self-Test high RPM check
13 r Cannot control RPM during Self-Test low RPM check
14 c PIP circuit failure
15 o ECA Read Only Memory (ROM) test failed
15 c ECA Keep Alive Memory (KAM) test failed
18 r SPOUT circuit open
18 c Erratic IDM input to processor
19 o Failure in ECA internal voltage
21 or Engine Coolant Temp (ECT) out of Self-Test range
22 orc Manifold Absolute Pressure (MAP) out of Self-Test range
23 or Throttle Position (TP) out of Self-Test range
24 or Air Charge Temp (ACT) out of Self-Test range
28 c Loss of IDM - right side
29 c Insufficient input from Vehicle Speed Sensor (VSS)
31 orc EVP circuit below minimum voltage
32 orc EVP voltage below closed limit
33 rc EGR valve opening not detected
34 orc EVP voltage above closed limit
35 orc EVP circuit above maximum voltage
41 r HEGO sensor circuit indicates system lean
41 c No HEGO switching detected
42 r HEGO sensor circuit indicates system rich
48 c Loss of IDM - left side
51 oc ECT indicated -40°F/circuit open
52 o Power Steering Pressure Switch (PSPS) circuit open
52 r PSPS circuit did not change states
53 oc TP circuit above maximum voltage
54 oc ACT indicated -40°F/circuit open
61 oc ECT indicated 254°F/circuit grounded
63 oc TP circuit below minimum voltage
64 oc ACT indicated 254°F/circuit grounded
67 o Neutral Drive Switch (NDS) circuit open or A/C on
72 r Insufficient MAP change during Dynamic Response Test
73 r Insufficient TP change during Dynamic Response Test
74 r Brake On/Off (BOO) circuit failure or not actuated during Self-Test
77 r Operator error (Dynamic Response/Cylinder Balance tests)
84 o EGR Vacuum Regulator (EVR) circuit failure
86 o Shift Solenoid (SS) circuit failure
87 oc Primary Fuel Pump circuit failure
88 o Loss of Dual Plug input control
89 o Clutch Converter Override (CCO) circuit failure
95 oc Fuel pump circuit open; ECA to motor ground
96 oc Fuel pump circuit open; Battery to ECA
98 r Hard fault is present (currently in FMEM)
NO CODES Unable to initiate Self-Test or unable to output Self-Test codes
CODE NOT LISTED Service codes displayed are not applicable to vehicle being tested
(1) Conditions: "o" = On-Demand (KOEO) Code, "r" = Engine Running (KOER) Code, "c" = Continuous Memory Code
Factory Service Tools

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When to See a Mechanic

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  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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