Parts
$50–1200
P0606 — PCM / ECM Processor Fault
CAUTIONIs it safe to drive? The engine computer flagged an internal fault. Can cause erratic running; have it checked — but verify power/grounds before condemning a computer.
What P0606 means
The powertrain control module reported an internal processor or self-test failure. Real ECM failures happen, but bad grounds and low voltage cause this far more often.
Most likely causes (in order)
- Poor ECM ground or power supply (check FIRST)
- Corroded ECM connector
- Water intrusion
- Actual ECM internal failure (rare)
Symptoms you might notice
- Erratic running / stalling
- Multiple unrelated codes
- No-start
What to check first
Before buying a computer: clean and verify all ECM grounds and power feeds, inspect the connectors for corrosion/water. Most 'bad ECM' codes are really power/ground problems.
Repair cost & difficulty
Labor
0.5–3 hr
Difficulty
Moderate