P1502high severityPowertrain
Theft Deterrent System - No Password Received
on 2002 Chevrolet Impala 3.8L V6 · FWD
What this code means
The PCM did not receive the expected security password from the Body Control Module (BCM) or Vehicle Theft Deterrent module. The theft deterrent system disables the vehicle if the correct key/password is not verified.
Symptoms
- Vehicle will not start
- Check Engine Light
- Security light flashing
- Engine cranks but does not fire
- Intermittent no-start condition
Common causes
- Faulty ignition key or key transponder
- Passlock sensor failure
- Body Control Module (BCM) malfunction
- Wiring issue between BCM and PCM
- Ignition lock cylinder failure
Diagnostic steps
- Attempt start with known-good key
- Check security system indicator light status
- Test communication between BCM and PCM
- Inspect Passlock sensor connector
- Check for BCM-related codes
Repair notes
Try 10-minute relearn: turn key to ON for 10 minutes until security light stops flashing, then turn off and restart. If persistent, replace Passlock sensor or BCM.
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Other Powertrain codes on this vehicle
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P0002
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P0003
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P0004
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P0010
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P0011
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P0012
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P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1