P0602: Control module programming error

What P0602 means

The ECU needs the right software and data loaded for that specific car. This code means that programming is missing or not the correct one. It often shows up after fitting a new or second-hand ECU, or when an update was interrupted.

Most common causes

• Replacement ECU not programmed or not matched to the car
• Software update interrupted or incomplete
• Low battery during programming
• Modified software that does not match the car
• Internal ECU fault

Symptoms

• Engine warning light on
• Engine may not start
• Limp mode or lack of power

Can you drive with P0602?

With care If it starts and runs well you can drive carefully to a garage, but it might leave you stranded. It needs programming equipment.

How to check it

If the ECU was recently replaced or updated, tell the garage: that is almost certainly where the problem lies. This repair needs the manufacturer’s programming tools, so it usually means a specialist or the dealer.

How to read and clear P0602 with Final OBD

Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P0602 with this same explanation and whether it’s confirmed, pending or permanent.

With Free you read this code with its short description for nothing, and clear it if the engine stores it over standard OBD. With Pro you get the full explanation, how the car was running when it was logged (revs, temperature, load) and clearing in every control unit.

Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before the ITV. It’s all in how to read and clear fault codes and in the ITV and OBD.

Similar codes

• P0600 Serial communication link fault
• P0601 Internal control module memory checksum error
• P0603 Internal control module keep alive memory (KAM) error
• P0604 Internal control module random access memory (RAM) error
• P0605 Internal control module read only memory (ROM) error
• P0606 ECM/PCM processor fault
• P0607 Control module performance
• P0615 Starter relay: circuit fault
• P0616 Starter relay: circuit low
• P0617 Starter relay: circuit high

P0602 is a generic code, so it means the same on any make, for example on Abarth, Cupra, Jeep, Mini, Nissan, Seat. See what Final OBD does on your car in makes and models.