How to Troubleshoot Circuits at the PCM Connectors

WARNING: This page is about a different car, the 2013 Acura MDX, 2012 Acura MDX, 2011 Acura MDX, and 2010 Acura MDX. 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 up to an hour 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 auxiliary under-hood fuse/relay box (A) from the stay (B), then remove the bolt (C).

Fig 1: Identifying Auxiliary Under-Hood Fuse/Relay Box
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Remove the bracket (D), then free the A/C discharge line (E) from the clip (F) and remove the A/C suction line mounting bracket bolt (G).

Fig 2: Locating Bracket, A/C Discharge Line, Clip And A/C Suction Line Mounting Bracket Bolt
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Remove the cover (H), then disconnect PCM connectors A, B, and C.
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: Locating Terminal Test Port (A) Of PCM Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Connect one side of the patch cord terminals (A) to a commercially available digital multimeter (B), and connect the other side of the patch cord terminals (C) to a commercially available banana jack (Pomona Electronics Tool No. 3563 or equivalent) (D).

Fig 4: Checking PCM Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Gently contact 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. 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.