dont know where to start dome light flashes non stop and clickibg of relay behind dash is dridriving me insane. please some one help me on figuring whats going in here

 

Welcome to the forum millwright4u2,

I've moved your question from General Tech Help to XJ40 forum. Members here with the same model will be able to help.

Please follow this link New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum to the New Member Area - Intro a MUST forum and post some info about yourself and your vehicle for all members to see. In return you'll get a proper welcome and some useful advice about posting to the forum.

Graham

 

Hi millwright4u2,

Welcome to the Jaguar Forums! It's great to have you with us.

You can download the 1991 XJ Electrical Guide at the link below, courtesy of our forum member Gus and his website, jagrepair.com:

1991 XJ Electrical Guide


The schematic for the interior lighting is on Figure 9, or pdf page 27.

The Door Guard Light Relay is behind the glove box, so if that's where you're hearing the clicking it would be worth checking that out.

An intermittent door switch might cause your symptoms.

The Central Microprocessor (CPU) is directly involved in lighting functions, and one common issue is water ingress into the CPU due to clogged A/C drains that allow water to pool below the evaporator in the center console climate control unit and to slosh over onto the CPU when the vehicle makes left-hand turns.

Hopefully someone else has dealt with the exact same issue and will be able to give you more specific direction.

Cheers,

Don

 

Is it a regular flashing? It the relay clicking With the light? I would check the door switches first. Maybe a wire has come loose one of them.

 

Thats going to be the key, I think. Does the car have a dealer-installed or aftermarket alarm system, or remote starter?

The alarm modules often have outputs that will flash the interior lights when the system is triggered.

Also, the CPU, or one of its inputs could potentially cause a regular flashing.

If it's flashing at an erratic interval, that would definitely suggest a wiring or switch fault. Something is providing ground to that relay. Could be a defective door switch, dash-mounted light switch, alarm module, faulty CPU, or any of the associated wiring.

Nick

 

The forum keeps tripping up and losing everything I have written - so, I will have another go. I don't know what it is doing - it just goes white, bit other tabs are fine, so I don't think it is me.

Anyway,

Do the interior lights flash on and off very fast like a strobe light, together with the relay clicking equally fast and in time with it? Does the strobe effect trigger when an individual door is opened, with the other doors turning the interior lights on as normal - or do the interior lights flash when all the doors are opened?

If strobe light flashing is caused by opening individual doors rather than all of them, then I suspect you have a faulty door ajar microswitch attached to the the door latch of that particular door. The microswitch can become contaminated with grease over the years and fail. Sometimes, cleaning the microswitch with contact cleaner can make it work properly. If this does not work, then you will need to fit a new microswitch to that particular door latch.

The door ajar microswitches are sided/front and rear - so you will need to get the correct one (though I suspect the microswitch part itself will be a generic microswitch).

For a 1991 car, the part numbers are:

Front left: DBC11589
Front right: DBC11588

Rear leftBC11611
Rear rightBC11610

Genuine Jaguar Parts and Jaguar Accessories for classic Jaguars from Jaguar Classic Parts UK

 

I don't know what the random green grin things are doing there! Odd!

The part numbers are DBC11611 and DBC11610.

 

The HTML code for the "random green thing" smiley is [colon capital D] so almost the same as what you wrote - I think the use of a space may increase or decrease the chances of this occurring - anyway, I found it quite amusing so no worries!



Larry