P0602 code meaning
Control Module Programming Error
Powertrain system Generic code P06xx codes Check engine light
What P0602 means
P0602 reports that the module is not, or not completely, programmed for this vehicle. GM checks at power-up and then every second whether a service replacement module still carries no calibration, and sets the code in the first trip; in brake modules a missing calibration set or a sensor ID that does not match also counts. Ford uses P0602 when the checksum of the vehicle identification block (tire size, axle ratio, VIN) is wrong. Typical triggers are a new module that was never programmed, a reflash interrupted by a voltage dip or lost connection, or wrong software. Depending on the maker the engine may not start, run with reduced power or only show the lamp; GM Europe engines show a service lamp instead of the check engine light. The fix is almost always reprogramming with a stable power supply; replace the module only if the code returns.
P0602 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0602
- Check engine light or service lamp
- Engine may not start or runs in limp mode
- Reduced engine power
- Appears right after a module replacement or software update
Common causes of P0602
- Most likelyModule replaced and not (completely) programmed
- Most likelyProgramming interrupted by a voltage dip or lost connection
- PossibleWrong or incompatible software, calibration or configuration block
- Less likelyInternal memory defect in the module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Engine control moduleControl module power supplyControl module ground
What each part of P0602 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 6 | Area: computer (engine control module) and output circuits. |
| 02 | The exact fault in that area. |
What to do next
- Note P0602 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0602
What does P0602 mean?
P0602 means "Control Module Programming Error". P0602 reports that the module is not, or not completely, programmed for this vehicle. It is a generic code, so it means the same on every make.
Is it safe to drive with P0602?
Drive gently and only to a workshop. With P0602 the car can go into limp mode (reduced power) to protect itself.
Will P0602 fail an emissions test?
Yes, it can. P0602 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0602 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. This is a job for a workshop.
Will P0602 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.