How to Troubleshoot Circuits at the PCM Connectors

WARNING: This page is about a different car, the 2011 Honda Insight and 2010 Honda Insight. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: The PCM overwrites data and monitors the EVAP system for about 30 minutes after the ignition switch is turned to LOCK (0). Jumping the SCS line after turning the ignition switch to LOCK (0) cancels this function. Disconnecting the PCM during this function, without jumping the SCS line first, can damage the PCM.

Jump the SCS line with the HDS.
Remove the cover (A).

Fig 1: Identifying PCM Cover
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Remove the bolts (D).

Fig 2: Identifying PCM And Connectors
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Disconnect PCM connectors A, B, and C, then remove the PCM (E).
NOTE: PCM connectors A, B, and C have symbols (A=■, B= , C=◦) embossed on them for identification.
When diagnosis/troubleshooting is done at the PCM connector, use the terminal test port (A) above the terminal you need to check.

Fig 3: Identifying PCM Connector Terminal Test Port
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Connect one side of the patch cord (A) terminals to a commercially available digital multimeter (B), and connect the other side of the patch cord terminals to a commercially available banana jack (Pomona Electronics Tool No. 3563 or equivalent) (C).

Fig 4: Connecting Digital Multimeter To PCM Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Gently insert the pin probe (male) into the terminal test port from the terminal side. Do not force the tips into the terminals.

NOTE:

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.