It sounds like you're dealing with a security or immobilization issue in your 1990 Jaguar XJS that's preventing it from starting. Given the symptoms you've described, it's possible that the security system might be causing this problem. Here are a few steps you can take to try to reset the system and potentially resolve the issue:
Disconnect and Reconnect the Battery: Disconnect the car's battery and leave it disconnected for about 15-30 minutes. This can sometimes help reset the vehicle's electronic systems, including the security system. After the waiting period, reconnect the battery and see if the issue is resolved.
Try a Different Key: If you have access to multiple keys for the vehicle, try using a different key to see if that makes any difference. Sometimes, a problem with the key's transponder or security code can cause starting issues.
Lock and Unlock the Car Manually: Lock and unlock the doors of the car manually using the key rather than the remote. This can sometimes reset the security system and allow the car to start.
Check for a Valet Mode: Some vehicles have a valet mode that can be triggered accidentally. This mode can limit certain vehicle functions, including starting. Check your owner's manual to see if your Jaguar has this feature and how to disable it.
Check the Owner's Manual: Consult the owner's manual for any information regarding security system reset procedures or troubleshooting steps specific to your vehicle model.
Professional Diagnostics: If the above steps don't resolve the issue, it might be necessary to consult a professional mechanic or a Jaguar dealership. They have access to specialized diagnostic equipment that can help identify and resolve complex security system issues.
Aftermarket Alarm System: If you suspect that an aftermarket alarm system might be causing the problem, it's possible that the system was installed discreetly. Check for any additional wiring or components that might not be factory-standard. If you find an aftermarket system, you might need to consult its documentation or seek professional help to disable or reset it.
Aug 12, 2023 at 3:54 PM
