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2001 Jeep Cherokee 4.7L V8 P0352 Fault: Coil Circuit Short, PCM Issues, and Wiring Diagnosis

Model: 2001 Jeep Cherokee Fault Code: P0352 Posted: 2018-06-04 10:16

I'm experiencing a persistent P0352 diagnostic trouble code on my 2001 Jeep Cherokee with the 4.7L V8 engine. The issue appears to stem from a melted wire connection at the coil connector. I've already replaced the spark plug and installed a known-good coil, but still see the P0352 code. After testing, there is no continuity between the coil's primary wire and battery power when connected to the new connector (wired with heat shrink). A 5V signal is detected at the coil terminal while the engine is running using a digital voltmeter (DVA), and I confirm that pin #9 has continuity to the connector. Battery voltage is present on the battery feed side of the connection. Despite these checks, no power is observed on the control circuit when the plug at the PCM is disconnected. I've also found foaming oil residue in the spark plug hole—cleaned it out with compressed air before reinstallation. I'm wondering if there's a short elsewhere in the harness or whether the issue lies within the PCM itself. Any guidance would be greatly appreciated.

Related fault codes
P0352
Comments (8)
Anonymous 2018-06-04 16:30

Use a test light at the same point where you observed 5V during engine operation. The light should pulse, indicating that the Powertrain Control Module (PCM) is actively sending a control signal. If it doesn't pulse, this may indicate a faulty PCM driver circuit.

Anonymous 2018-06-05 13:17

Hi cj1 — I tested the coil connector on cylinder #2 by placing a test light between pins #1 and #2 at the coil end. When running, pin #1 shows a steady light, while pin #2 pulses. Before this, I installed a rebuilt PCM from Davie, FL, which smoked and burned out during operation. After removing it, I reinstalled the original PCM — it runs fine except for the P0352 code and exhibits rough idle. The two wires leading to the #2 coil connector were visibly melted together. I replaced the connector at a junkyard and blew out foam oil residue from the spark plug hole using compressed air before reinstalling. Does this suggest a deeper wiring or PCM issue?

Anonymous 2018-06-05 16:14

Resolving P0352 is critical. The fact that your rebuilt PCM from Davie, FL burned out raises concern about whether the #2 coil circuit was faulty — if so, verify that the positive (B+) side of the coil does not short to the control side. When measuring voltage across the coil connector, ensure the test probes do not touch each other, as this could cause a direct short from battery power to the PCM driver circuit, leading to excessive current draw and component failure. The oil residue in the spark plug hole is likely harmless — just clean it out thoroughly. Consider running the engine for a few revolutions with the plug removed to clear any cylinder buildup.

Anonymous 2018-06-06 13:22

Hi cj1, thank you for the input. I'm now measuring battery voltage on the coil driver wire at the connector — it's present — but I can't locate where a short is occurring. Could the issue be in the wiring harness downstream of the melted connection at the coil connector?

Anonymous 2018-06-06 15:00

I've traced the harness from the coil connector to the PCM plug and confirmed that the tan-with-pink wire (coil circuit) is not shorted to the white PCM plug. The issue may be either in the PCM plug itself or within the PCM module. When I installed the rebuilt PCM from Davie, FL, it smoked and burned out — along with the coil. Additionally, when the PCM plug is disconnected, there's no voltage at the coil connector. This suggests a potential internal failure in the PCM or an open circuit in the control path.

Anonymous 2018-06-06 15:16

Yes, I confirm battery voltage is present on both wires at the coil connector when measured directly. However, with the #1 coil (a known good one), I do not observe battery voltage on either side of the coil — even during engine operation.

Anonymous 2018-06-07 05:48

If the PCM control circuit is grounded continuously, it will cause excessive current flow through the coil and lead to overheating or failure. With the key ON and engine OFF, there should be full battery voltage across both terminals of the coil (measured from coil terminal to ground). During engine operation, the PCM pulses the control side to ground. If the control circuit is grounded incorrectly due to a faulty PCM driver, it will draw maximum current through the coil — causing burnout. For reference, consult bbbind.com for detailed ignition system schematics to help identify and troubleshoot this circuit.

Anonymous 2018-06-07 07:16

Thanks for the clarification! I confirm that with the key ON and engine OFF, neither side of the #1 coil (a known good one) shows battery voltage — even when measured from the coil terminal to ground. This contradicts expected behavior and suggests a deeper issue in the power or control circuit, possibly related to the PCM or wiring integrity.