How to Troubleshoot Circuits at the PCM Connectors
How to Troubleshoot Circuits at the PCM ConnectorsNOTE: The PCM overwrites data and monitors the EVAP system for up to 15 minutes after the ignition switch is turned OFF. Jumping the SCS line after turning the ignition switch OFF cancels this function. Disconnecting the PCM during this function, without jumping the SCS line first, can damage the PCM.
1. Jump the SCS line with the HDS.
2. Remove the PCM cover (A). Disconnect the PCM connectors (B), and probe the terminals from the terminal side of the connectors.
3. Check the connector terminal diameter, and select the suitable pin probe (male).
4. When diagnosis/troubleshooting is made at the PCM connector, use the measurement hole (A) above the terminal you need to check.
5. Connect one end of the patch cords (A) to a commercially available digital multimeter (B), and connect the other patch cord terminals to commercially available banana jacks (Pomona Electronics Tool No. 3563 or equivalent) (C).
6. Gently slide the pin probe (male) at the connector terminals from the terminal side. Do not force the tips into the terminals.
NOTICE
^ For accurate results, always use the pin probe (male).
^ To prevent damage to the connector terminals, do not insert test equipment probes, paper clips, or other substitutes as they can damage the terminals. Damaged terminals cause a poor connection and an incorrect measurement.
^ Do not puncture the insulation on a wire. Punctures can cause poor or intermittent electrical connections.