fast cars said:
Hi Steve, its a 99 V Jag Sov 4.0 LWB, have gone along with your instruction, go the J gate light to flash but got no beep from the alarm tried a few times again and just got as far as flashing LED again. Then got out of car and some how the control worked to lock it. Then tried to open and close a few times and its really unreliable, contacts cleaned and batts new, do I need a new transmitter?
Possibily. You've obviously done something if the transmitter now works intermitently.
Firstly does the alarm sounder work? If not the sounder may have failed and that's why you don't hear the beep. Lock the car with the key then unlock and open the drivers door. You should hear a warning chime which calls for you to put the key in the ignition and turn to position 2. Ignore this and 10 seconds later the alarm will trigger flashing the indicators, honking the car horns and the alarm sounder which is a high pitched beeping noise.
If you do hear the sounder then repeat the whole procedure with all the transmitters you have just to make absolutely sure you're doing it right. If not then there's a fuse on the sounder power supply - can't remember where, but IIRC it takes out some other function as well - that may have gone and I have heard cases of sounders failing too. You could try disconnecting the sounder supply - it's under the bumper - and substuting a 12v bulb as a quick check. BUT you're going to a place I'd choose not to with XJ8 electrics by doing so, so that's up to you.
If none of that works then I'd suggest either taking a gamble on another tranmitter or taking the car to a Jaguar indy who can diagnose the problem. The other alternative is do nothing and just lock and unlock the car manually.