C0420high severityChassis
Pre-Collision System Malfunction
on 2014 Jeep Cherokee 3.2L V6 · AWD
What this code means
General fault in the pre-collision system that prepares or initiates emergency braking.
Symptoms
- Pre-collision system warning light
- Automatic emergency braking disabled
- Forward collision alert unavailable
- Driver assist systems degraded
Common causes
- Radar or camera sensor fault
- Control module failure
- Brake system fault preventing intervention
- CAN communication error between modules
Diagnostic steps
- Check for radar and camera codes first
- Verify brake system is fully operational
- Test CAN communication between PCS modules
- Check all sensor alignments
- Inspect wiring to PCS components
Repair notes
Diagnose root sensor or communication fault. PCS depends on multiple subsystems.
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C0021
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C0021
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C0023
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C0023
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C0025
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C0025
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