U0254: Lost Communication With Remote Start Module
What to do
The car drives and starts normally with the key. Only the remote starting has stopped.
Before assuming a fault, check the things the system deliberately refuses on — there are a lot of them, and any one will stop it:
- Is the bonnet properly shut? A bonnet the car thinks is open blocks remote start and may cause no other symptom at all.
- Is the check engine light on? Most systems will not remote start while another fault is present, so fixing that may bring it back.
- Have you already used it? Most systems allow only one or two remote starts before the key must be used, and shut the engine down after ten or fifteen minutes. That is normal, not a fault.
If remote start was fitted after you bought the car, start with the installer rather than a main dealer. Aftermarket systems are wired into the vehicle's own circuits and are much likelier to be the problem than the car is.
What this code means
The remote start module has stopped being heard from. See U0200 for the block's framing.
Remote start lets an engine be started without anybody in the vehicle, which is why the module is surrounded by more interlocks than almost anything else on the body network. Before it will act, it must confirm the vehicle is locked, the bonnet is shut, the gearbox is in park, the alarm is set, no fault is present, and — on manual vehicles where it is offered at all — that a defined procedure was followed to prove the gearbox is in neutral. Any one of those unmet, and it refuses.
That makes "remote start has stopped working" a complaint with a long list of innocent explanations, and it is worth working through them before anything is diagnosed:
- The bonnet switch — the same switch discussed at U0219. If the vehicle thinks the bonnet is open, remote start is inhibited, and nothing else may be affected.
- An existing fault elsewhere. Many systems refuse to remote start while a check engine light is on.
- A limit on consecutive starts. Most systems allow only one or two remote starts before requiring the key to be used, specifically so a vehicle cannot idle indefinitely unattended.
- A run-time limit that shuts the engine down after ten or fifteen minutes, which is normal behaviour rather than a fault.
On a factory system this module is usually part of the vehicle's own security architecture, so a fault here can accompany immobiliser and alarm symptoms. On an aftermarket installation — which is very common for this feature — the U0248 reasoning applies in full: the installation is the first suspect, not the vehicle.
Nothing here affects driving or normal starting with the key.
Likely causes
Start here
Less common
- Module not coded to the vehicle · specialist
- Damaged data bus wiring · moderate
- Failed power or earth supply to the module · moderate
Symptoms
Components involved
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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