Tech Forum

I'm troubleshooting an electrical issue on my S13 KA24DET using a Wiring Specialties Pro chassis and engine harness, Link ECU, and PDM15 with an 8-button CANbus keypad and digital dash.

The original PDM experienced issues after I discovered a connector filled with water, with corroded pins and a slight burnt smell. I subsequently found that the PDM was not supplying proper 12V to the C6 output on the green connector.

I replaced the PDM and reloaded the configuration file. The replacement worked for approximately five laps on track before the keypad and digital dash shut off again.

Current symptoms and findings:

• C6 is commanded ON in the PDM software but measures 0V.

• I've confirmed 0V directly at the PDM's C6 output pin and at the keypad/dash end of the harness.

• The keypad and digital dash both function when powered directly from 12V.

• Both PDMs have exhibited the same C6 failure.

• I recently discovered the alternator was failing, with a faulty pulley and approximately 12V while running. After replacing it, the charging voltage is now approximately 14V, but the C6 issue persists.

I'm trying to determine whether the failing alternator could have damaged both PDMs, whether there may be a fault or excessive current draw on the C6 circuit, or whether another issue could cause the output to show ON in the software while supplying 0V.

Has anyone experienced a similar failure, or can the manufacturer advise on the best diagnostic procedure to determine whether C6 is internally damaged or being disabled by protection logic?