x350 2005 55 V6 petrol, rear electronic module seems rear module not working to start car ! . code is U1262 (J1850) COMMUNICATIONS BUS FAULT, all fuses in boot ok, car not seeing key code, unlock & lock ok & alarm red ight above dash, module is "2W9F-AH" both keys before programming which need to know location please and can one of same number be programmed ?? i had the car connected to thinkcar dongle i tried re program the key chip but asking for a 4 digit code ?? ( just had an update on the software for immobiliser ) has changed how it works also added the code needed part - last time it worked perfectly to add a key, also had to erase the chip code in key before trying to reprogram 2 keys.... DSC code received too
going to look tomorrow at fuses in engine bay and earths , battery is fairly new exide which has performed well
has been driving fine before this, now actually starts but shuts down immediately
any info appreciated
thanks

 

REM puts out fuel pump power as requested by the ICM. No SCP com allows the car to run on initial pressure application then runs out since the REM is not getting the pump request.

 

So you have added an immobilizer and the problem started? So the Immobilizer is not allowing the fuel pump to continue to run after teh key returns to Position 1 as OldKarz wrote. Fix the immobilizer installation / setup to be compatible with your dealer installed options.

 

hi guys thanks for the replys, the thinkcar diag unit after update would not programe the keys , the guy at local garage used his launch unit to sort it no charge, it was super easy with thinkcar before the update .. seems no point paying for the immobiliser tool which downloads after paypal payment, not expensive approx £7.
its a good platform just a dongle and app, ive used it for air suspension-ddm-release rear brakes for disc + pad change however seems the immobiliser now useless.
the rem code threw me but obvious it wanted the code added.
again thanks for help learning curve goes on.