Probe – Accessing codes
With Analog Voltmeter
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LLC.
NOTE: Correct results of the Quick tests are dependent on the proper operation of related non-EEC components. It may be necessary to disconnect or disassemble harness connector assemblies to do some of the inspections. Pin locations should be noted prior to disassembly.
- Perform the following safety precautions to start and run vehicle tests.
- Apply parking brake.
- Place gear select lever into PARK (A/T) position (NEUTRAL on M/T).
- Block drive wheels.
- Inspect the air cleaner and inlet ducting.
- Check all engine vacuum hoses for damage, leaks, cracks, blockage, proper routing, etc.
- Check EEC system wiring harness for proper connections, bent or broken pins, corrosion, loose wires, proper routing, etc.
- Check the Electronic Control Assembly (ECA), sensors, and actuators for physical damage.
- Check the engine coolant for proper level.
- Check the transmission fluid level and quality.
- Make all necessary repairs prior to continuing with test preparation.
- Turn OFF all electrical loads (radio, lights, A/C-heater blower fans, etc.)
- Turn the ignition switch OFF.
- Connect analog voltmeter positive (+) lead to the EEC STO terminal of the diagnostic connector and the negative (-) lead to engine ground.
- Jumper EEC STI of the diagnostic connector to engine ground.
- Set the analog voltmeter on a DC voltage range to read from 0 to 20 volts.
Key on Engine Off test
Using Analog Voltmeter or Check Engine Light
- START engine and bring up to operating temperature.
- Turn the key OFF, wait ten seconds.
- Turn analog voltmeter ON. Turn ignition key ON.
- Observe analog voltmeter needle sweeps for any code indications.
- Record all codes received.
- Turn the ignition key OFF. IF NO CODES ARE STORED AND ENGINE STARTS, proceed with Key On Engine Running Self Test.
Key on Engine running test
Using Analog Voltmeter or Check Engine Light
- Run engine at 2000 rpm for two minutes.
- Turn engine OFF, and wait 10 seconds.
- START engine.
- Run engine at idle.
- Jumper STI on diagnostic connector to ground.
- Record service codes.
NOTE: If codes received in Key ON Engine Off (KOEO) self test from the first time cannot be duplicated it may be necessary to tap suspected sensors, shake and wiggle component harness, or drive the vehicle in order to induce a failure.
Probe codes01
Ignition Diagnostic Monitor IDM
08
Vane Air Flow Meter VAF
09
Engine Coolant Temperature ECT
10
Vane Air Temperature VAT
12
Throttle Position Sensor TP
14
Barometric Pressure Sensor BP
15
Exhaust Gas Oxygen EGO
16
EGR Valve Position EVP
17
Exhaust Gas Oxygen EGO
25
Solenoid Controlled By Ground SCG
26
Solenoid Controlled By Ground SCG
28
Solenoid Controlled By Ground SCG
34
Solenoid Controlled By Ground SCG