Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
How to Troubleshoot Circuits at the PCM Connectors
Special Tools Required ('20-21)Β
Pin Probe Male 07ZAJ-RDJA110Β
NOTE:Β The PCM stays on for up to an hour after the vehicle is turned to the OFF (LOCK) mode. Jumping the SCS line after turning the vehicle to the OFF (LOCK) mode 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, and wait more than 1 minute.
3. When diagnosis/troubleshooting is done at the PCM connectors, use the terminal test port (A) above the terminal you need to check.
'17-19Β
'20-21Β
4. '17-19: Connect one side of the patch cord terminals (A) to a commercially available digital multimeter (B), and connect the other side of the terminal (C) to a commercially available banana jack (Pomona Electronics Tool No. 3563 or equivalent) (D).
5. '20-23: Connect one side of the patch cord terminals (A) to a commercially available digital multimeter (B), and connect the other side of the terminal (C) to the pin probe male.
Gently contact the pin probe (male) at the terminal test port from the terminal side. Do not force the tips into the terminals.
NOTICE:Β
- 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 or eventually lead to poor or intermittent electrical connections.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.