Pinpoint Test D: DTC U0100:87

D1 CHECK THE BATTERY STATE OF CHARGE
- Check the battery state of charge with the battery condition test. Refer to BATTERY, BATTERY MOUNTING & BATTERY CABLES article.
- Does the battery pass the battery condition test?
- Yes : GO to D2.
- No : REFER to CHARGING SYSTEM article to diagnose the low battery voltage condition.
D2 CHECK FOR MODULE COMMUNICATION ON THE HS-CAN
- Carry out the network test using the scan tool.
- Is the scan tool unable to communicate with any of the modules on the HS-CAN?
- Yes : REFER to MODULE COMMUNICATIONS NETWORK article to diagnose the module that is not communicating with the scan tool.
- No : GO to D3.
D3 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the PCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new PCM. REFER to ENGINE CONTROLS - ELECTRONIC ENGINE CONTROLS article. CLEAR the DTCs. REPEAT the self-test. If the concern is still present, GO to D4.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
D4 CHECK FOR CORRECT RFA MODULE OPERATION
- Disconnect all the RFA module connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-out pins
- Connect all the RFA module connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new RFA module. REFER to MULTIFUNCTION ELECTRONIC MODULES article. CLEAR the DTCs. REPEAT the self-test.
- No : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.