Electrics: FOB Does Not Work

[Samit Naik]

I have 2007 XC90 D5 RHD the issue is that at first the range became less and was working standing really close to the car holding the remote on the glass.

Now everything stopped. After using the key even the red blinker on the dashboard does not work.

I have changed the battery of the FOB but still the same.

May I know where is the fuse to this? and also the module that receives the signals?

May be I can clean out the moisture.

[SwissXC90]

The remote key fob antenna is in the rear view mirror, and the mirror is coded to the car.

If you have 2 x keys and both keys perform identically, then it must be an interference problem or a failure in the rear view mirror.

Check that you have no accessories in your car that might interfere.
Unplug any DAB radio, USB chargers, cameras, etc
Check performance at different locations (home, supermarket, work, etc) to see if you have a local interference problem at one location.

If you have ruled out all other possible sources, then the solution is a new rear view mirror from the dealer. You cannot fit 2nd hand mirrors due to the coding requirements.

[Samit Naik]

Thanks A lot , I just tried sometime back it started to work from close proximity. I will check my car for any kind of interference. Do you know where is the security module located in the car?

[SwissXC90]

What do you mean by "security module"?

The key fob talks to the Upper Electronics Module (UEM), which is the Rear View Mirror, to lock/unlock the car

The key immobiliser talks to the Central Electronics Module (CEM) and the Engine Control Module (ECM) to authorise vehicle start

The entire car is monitored by an alarm system (if fitted) which is part of the Rear Electronics Module (REM) and includes a siren module. The alarm also uses the CEM and other modules as well.

[Samit Naik]

Originally Posted by SwissXC90

What do you mean by "security module"?

The key fob talks to the Upper Electronics Module (UEM), which is the Rear View Mirror, to lock/unlock the car

The key immobiliser talks to the Central Electronics Module (CEM) and the Engine Control Module (ECM) to authorise vehicle start

The entire car is monitored by an alarm system (if fitted) which is part of the Rear Electronics Module (REM) and includes a siren module. The alarm also uses the CEM and other modules as well.

Could you tell me where is the REM located?

[john langrick]

Hi, mine is an earlier car but rem is rear electronic module and on mine it is behind the left hand panel looking into the back. Remove the quadrant piece that covers the rear light and you should be able to pull out the panel between that and the wheel arch.

Hope this helps
John l

[Samit Naik]

yes found it and cleaned the ports!!! Thank you!!!