PCM Internal Dual-Port Communication Failure
Table of contents
P1603 JEEP Possible Causes
- Powertrain Control Module (PCM) fused ignition switch circuit
- Faulty PCM
- PCM harness is open or shorted
- PCM circuit poor electrical connection
How do I fix code P1603 JEEP?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Tech Notes
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Cost of diagnosing the P1603 JEEP code
The cost of diagnosing the P1603 JEEP code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P1603 JEEP Description
With the ignition off, on, and run/start the Powertrain Control Module (PCM) monitors the communication with the Ignition Switch Output circuit. The Diagnostic Trouble Code (DTC) will set when the PCM detects an intermittent open circuit between the PCM connector and the Fused Ignition Switch Output circuit.