Operation CHARM: Car repair manuals for everyone.

Component Inspection





Component Inspection

Check Main relay
1. IG "OFF".
2. Disconnect the main relay.
3. Measure the resistance between battery power supply and control terminals of main relay. (Measurement "A")
4. Measure the resistance between battery power supply and power supply to PCM terminals of main relay. (Measurement "B")
A. Specification : 70 - 120 Ohms









5. Is the measured resistance within specification ?
YES
1) Go to "Check Generator" procedure.
NO
1) Substitute with a known - good Main relay and check for proper operation.
If the problem is corrected, replace Main relay and go to "Verification of Vehicle Repair" procedure.
Check Generator
1. IG "OFF".
2. Check the tension of the belt.
3. Check Battery terminal and Generator B+ terminal for looseness, corrosion or damage.
4. Engine "ON".
5. Operate electric equipments (Head lamp, Hot wire, etc).
6. accelerate engine to 2000 RPM and measure the battery voltage.
A. Specification : Approx. 12.5V ~ 14.5V
7. Is the measured voltage within specification ?
YES
1) Substitute with a known - good PCM and check for proper operation.
If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.
NO
1) Substitute with a known - good Generator and check for proper operation.
If the problem is corrected, replace Generator and go to "Verification of Vehicle Repair" procedure.

NOTE: There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by PCM. After testing PCM on the vehicle, use this function to reuse the PCM on the others