Back to 1997 Cadillac DeVille

1997 CADILLAC DEVILLE

4.6L V8 NorthstarFWDAUTOMATICgas
2 active safety recalls on this vehicle — view recalls
Repairs0Labor593Torque2368Fluid6DTC680Battery0Maintenance0Recalls2
P0606critical severityPowertrain

PCM Processor Fault

on 1997 Cadillac DeVille 4.6L V8 Northstar · FWD

What this code means

The PCM has detected an internal processor error.

Symptoms

  • Check Engine Light
  • Erratic operation
  • Possible no-start
  • Multiple fault codes

Common causes

  • PCM internal failure
  • Power supply issue to PCM
  • Severe voltage spike
  • PCM overheating

Diagnostic steps

  1. Check PCM power and ground circuits
  2. Look for water or heat damage
  3. Check for voltage spikes
  4. Try PCM reprogramming

Repair notes

Usually requires PCM replacement. Check power and grounds first.

Other Powertrain codes on this vehicle

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