← code lookup·Faults by symptom

Alternator is not charging

With the engine running, the on-board network should read 27–29 V. Lower — the alternator, the belt, or the wiring. Higher — the voltage regulator, and this is more dangerous: overcharging boils the batteries dry and can knock out electronics.

Other codes for this system

What happens if you keep driving

Time you have: To the nearest safe stop

The electrical system is not holding voltage. While the engine runs the alternator carries it; shut it off and you may not restart.

Next the lights go, then modules start dropping out and false codes appear all over the truck. Get to somewhere with help without shutting the engine down.

That said, the manufacturer flags this code as critical — if in doubt, it is safer to stop and check on the spot.

What to check on the spot

Check the battery terminals and earth strap — corrosion and loose clamps throw false codes all over the truck. Running voltage should be 27–29 V.

Can I keep driving

The answer depends on the code, not the light. A yellow light is a warning; a red one means do not move. But even under a yellow light there are faults that require stopping right away — low oil pressure, overheating, lost brake pressure. Enter the code — the reference will tell you plainly whether to keep driving or stop.

Know the code number? Type it into the search — or paste the whole list from the scanner and we will show which fault is the real one.