Theft Deterrent Fuel Enable Signal Not Correct

What it means

This is a Chevrolet (GM) manufacturer-specific code, and the same number can mean something different on other makes. The engine computer (PCM) received a message from the theft deterrent system (Passlock or PASS-Key), but the code in it does not match the one it learned, so it refuses to enable the injectors. It usually appears after the engine computer or theft module was replaced without a relearn, or with a key or sensor that sends a wrong value.

Models covered: Chevrolet (GM) models with Passlock/PASS-Key theft deterrent, mainly 1990s–2000s.

Related codes: P1626U1000P0562P0606

Symptoms4

• The engine starts briefly and dies, or cranks without starting.
• Security light on the dash is on or flashing.
• The problem often starts after the engine computer or another module was replaced.
• The engine may start with one key but not with another.

Possible causes5

• An engine computer or theft module replaced without performing a relearn.
• A key with a mismatched or worn resistor pellet on PASS-Key systems.
• A Passlock sensor sending an unstable value due to damage or poor wiring.
• Low battery voltage disturbing communication during cranking.
• A Class 2 bus communication fault or a module fault.

How to diagnose5

1. Ask whether any module or key was replaced recently; this is the key clue.
2. Read codes from the engine computer and the body or theft module.
3. Try another original key, if available, to see whether the key is the cause.
4. Check battery voltage and the sensor wiring in the steering column.
5. Use a GM-capable scan tool to view theft system status and perform the relearn.

How to fix5

1. Charge or replace a weak battery.
2. Perform the theft code relearn per the service manual after any module replacement.
3. Replace a mismatched key with one of the correct value.
4. Repair the sensor wiring or replace the sensor if its value is unstable.
5. Clear the codes and start the engine several times to confirm the code does not return.

Repair cost

In Saudi riyals; the highlighted part is the expected range for this fault.

A relearn or battery is the low end, while dealer programming of a module or a new lock cylinder can exceed normal repair prices because special programming tools are needed.

Prices are rough estimates for common cars at independent workshops and vary with the car and the source of the part.
Prices last updated: September 2026

Frequently asked questions