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Retrieving Codes

The PGM-FI system's ECU is equipped with a self-diagnosis function. When an abnormality is detected, the PGM-FI warning light in the instrument panel comes on, and the self-diagnosis indicator in the ECU blinks. The LED on the body of the ECU will blink up to 13 times with a two second pause to indicate trouble codes. The warning light on the instrument panel will shut off when the ignition switch is off, codes will be stored in the ECU. If the problem persists, dashboard warning light will come on again.

If LED fails to light, check for blown Hazard fuse or open circuit in White/Yellow wire between ECU A17 terminal and Hazard fuse. If these check out, replace ECU. With ignition ON, warning light should come on for about 2 seconds. If lamp does not light, check for blown No. 5 fuse, open circuit in Yellow wire between No. 5 fuse and combination meter, open circuit in Green/Red wire between combination meter and control unit, open in Black wires between ECU A2, A4 and Ground 1 or blown warning light bulb.

TROUBLESHOOTING CODE CHART

No. Of LED Blinks Symptom Possible Cause
0 (1) Engine will not start Disconnected ECU ground wire, Faulty ECU
0 (2) Engine will not start, No particular symptom shown Loose or poorly connected power line to ECU, Disconencted control unit ground wire, Short circuit in combination meter or waring light wire, Faulty ECU
1 No particular symptom shown, Erratic idling (Erratic injector, coupler & wiring insufficient fuel) Disconnector oxygen sensor coupler, Spark plug misfire, Short or open circuit in oxygen sensor circuit, Faulty oxygen sensor, Faulty fuel system
2 No particular symptom shown or system does not operate Faulty ECU
3 Wet plug, Frequent engine stalling, Engine fails to pick up speed Disconnected manifold absolute pressure sensor coupler, Short or open circuit in manifold absolute pressure sensor wire, Faulty manifold absolute pressure sensor
4 No particular symptom shown or system does not operate Faulty ECU
5 Engine fails to pickup speed Wet plug Frequent engine stalling, Disconnected manifold absolute pressure sensor piping
6 High idle speed during warm-up, High idle speed, Hard starting at low temp Disconnected coolant temp. sensor coupler, Open or short circuit in coolant temp. sensor wire, Faulty coolant temp. sensor (thermostat housing)
7 Poor engine response to opening throttle rapidly, High idle speed, Engine does not rev up when cold Disconnected throttle angle sensor coupler, Open or short circuit in throttle angle sensor wire, Faulty throttle angle sensor
8 Engine does not rev up, High idle speed, Erratic idling Short or open circuit in crank angle sensor wire, Crank angle sensor wire interfering with spark plug wires, Crank angle sensor at fault
9 See 8 See 8
10 High idle speed, Erratic idling when very cold Disconnected intake air temperature sensor, Open or short circuit in intake air temperature sensor wire, Faulty intake air temperature sensor
11 No particular symptom shown or system does not operate Faulty ECU
12 Frequent engine stalling, Erratic or unstable running at low speed, No particular symptom shown Disconnected EGR control system coupler, Shorted or disconnected EGR control wire, Faulty EGR control system
13 Poor acceleration at high altitude, Hard starting at high altitude when cold Disconnected atmospheric pressure sensor coupler, Shorted or disconnected atmospheric pressure sensor wire, Faulty atmospheric pressure sensor.
(1) Dash warning light off.
(2) Dash warning light on.
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