P0602: Control module programming error
Control module programming error
Severity: Inspect soon
In both Isuzu Axiom complaints the vehicle lost all power on the highway after P0602, and TroubleCodes.net says a vehicle can go into limp mode or fail to start.
It gets more serious if:
- Stop: Stop driving if the engine stalls or warning lights come on together.
P0602 in short
P0602 means the engine control module found its stored programming does not match what it expects. A new, wrong or modified module is a typical cause, and a failed module is rare. Some vehicles run normally; others go into limp mode or will not start, so have it checked.
The control module runs on stored software and calibration specific to the vehicle. If the module finds a mismatch, it sets P0602.
TroubleCodes.net lists a new module that has not been programmed, the wrong module, a tampered module and a faulty module as causes. Delaware lists the code as a control module programming error.
Two 2004 Isuzu Axiom owners report P0602 followed by loss of power on the highway.
Most likely causes
Cause 1: New, wrong or reprogrammed module
Common general cause- Why it ranks here
- TroubleCodes.net lists these first, and they are the typical reason a module reports a programming mismatch.
- What would change this
- Rises if the module or tune was recently changed. Falls if the module is original.
Cause 2: Failed control module
Supported by vehicle data- Why it ranks here
- Both Axiom complaints involve a sudden loss of power with the code, which fits a module that has failed, although the sources do not confirm the repair.
- What would change this
- Rises if reprogramming does not help and the battery and grounds are good. Falls if reprogramming clears it.
Cause 3: Low battery voltage or poor grounds
Possible — needs testing- Why it ranks here
- TroubleCodes.net tells the technician to check battery voltage, terminals and grounds before blaming the module.
- What would change this
- Rises if voltage is low or a ground is loose. Falls if supply is solid.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Clear the codes, check battery voltage and terminals, and see whether the code returns.
IfThe code does not return after the battery and connections are corrected
It meansA low supply was likely the trigger.
IfThe code returns
It meansSee whether the module was recently changed.
Step 2: Ask whether the module or its software was recently replaced or tuned, then have a shop read the programming status.
Warning:Programming a control module with a weak battery can corrupt it. Keep a battery charger connected during the job.
IfModule was replaced or tuned
It meansIt likely needs programming for this vehicle.
IfModule is original and reprogramming does not help
It meansModule failure is likely.
Symptoms
- Check engine light
- Limp mode or no start Gets more serious: stop and have it checked.
- Sudden loss of power with all warning lights on Gets more serious: stop and have it checked.
How to fix
Step 1: Check that the battery terminals are tight and clean.
Parts and cost context
- Engine control module (ECM / PCM):A replacement module needs programming. Labour varies; get a quote.
Labor varies by vehicle and shop; get a quote before you approve a repair.
Compare used part prices on PartPriceGuideOn your vehicle
IsuzuYour car
2004 · Axiom
Supported by vehicle dataTwo 2004 Axiom complaints report P0602 followed by loss of power on the highway.
Related codes
P0602 questions
Can I clear P0602 myself?
You can clear it, but if the module has a mismatch it will return. A shop with a factory tool is needed.
Sources and review
- ODI 10703438: 2004 Isuzu Axiom, P0602 ECM programming error
- ODI 10554576: 2004 Isuzu Axiom, P0602 PCM error
- P0602 trouble code definition
- On-Board Diagnostic Trouble Codes (generic code title list)
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error