Component Inspection

ECM (PCM) check
1. IG "OFF".
2. Select "vehicle scopemeter" in the menu, and connect channel A of scantool with FR terminal of Alternator harness connector.
3. Connect Channel B of scantool with C terminal of Alternator harness connector.
4. Start engine and check the signal waveforms. (Compare the signal waveform of electrical loads ON with OFF)
  Specification : Refer to SIGNAL WAVEFORM & DATA
5. Are the measured signal waveforms of Alternator normal?
  YES
  - Go to "Alternator check" procedure.
  NO
  - Substitute with a known-good ECM (PCM) and check for proper operation. If the problem is corrected, replace ECM (PCM) and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
Alternator check
1. IG KEY "OFF".
2. Check the tension of alternator belt.
3. Check corrosion, damage or looseness of Battery terminal and Alternator terminal.
4. Start engine.
5. Operate electrical parts (Head Lamp, Defogger, etc) .
6. Measure the voltage at 2000rpm.
  Specification : Approx 12.5V ~ 14.5V
7. Is the measured voltage within specification?
  YES
  - Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage. Check for poor connections, and check the related circuit between ECM (PCM) and component thoroughly. Repair as necessary and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
  NO
  - Substitute with a known-good Alternator and check for proper operation. If the problem is corrected, replace Alternator and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.