Lighting & central locking problem

Mr Ward · Post by **Mr Ward** » Fri Nov 25, 2022 7:59 am

OK here's a weird one.

Drove the Z yesterday with lights and fog lights on in the morning,

Parked up and the central locking refused to work.
Tried both keys and nothing happened.
Jumped in the car in the afternoon and put the lights on, nothing happened no lights or main beam or fogs at the front of the car, it does however have side lights.
There was no background light on the dash clocks.
No indicator displays on the dash clocks yet the indicators are working.
Took it for a quick drive to the shops and the lights suddenly worked for 30 seconds then went off again as it was moving, however the background light on the clocks remained lit as soon as the lights went off.

Checked every fuse in the internal fuse box, none are blown. Are there any relays for the lights that could go faulty, or is it a module that could have a loose connection?
Any suggestions would be appreciated as it is needed on the road for Saturday nights Dj work.

grannyknot · Post by **grannyknot** » Fri Nov 25, 2022 11:59 am

I would start checking the gounds, there are at least 3 grounding points for the wiring harness in the engine bay, if they become corroded all kinds of weird things can happen.

Jas- USA · Post by **Jas- USA** » Fri Nov 25, 2022 4:04 pm

Odd electrical things could be tied to either a battery on the way out or a faulty ignition switch.

Mr Tidy · Post by **Mr Tidy** » Fri Nov 25, 2022 8:53 pm

Just a thought but can you adjust the speed of the heater fan?

If not it may have gone into "transport mode" - it's a common problem when the battery is getting tired.

Mr Ward · Post by **Mr Ward** » Mon Nov 28, 2022 10:12 am

Heaters are fully adjustable, Lights started working on their own and then turn off randomly. I now have the doors open image on the dash while all doors are closed. Dashboard lights and background lights randomly work. Also, lights may come on if I fail to miss a pothole so it may be a loose connection (possibly).

Mr Ward · Post by **Mr Ward** » Mon Dec 12, 2022 5:30 pm

Ignition switch changed, new battery also. Still have random lighting and dash warning lights randomly popping up. I think its time to go retro and bypass all the modern crap that just keeps failing. Lighting and central locking plus fog and boot release are going on a rocker switch panel in the middle of the dash. A bit drastic but when you get fed up of dealing with modern crappy solutions its time to strip it back to the bare bones and go old school. Also have no indicator flashers in the main lighting cluster by the clocks. Definitely the main body module that is screwing around.

enuff_zed · Post by **enuff_zed** » Mon Dec 12, 2022 5:39 pm

Do you think GM5 or the Light Control Module?
GM5 is about £40 to get repaired.
LCM can easily be swapped and will work.................... you either live with a tamper dot on the dash or get someone to code it.

Mr Ward · Post by **Mr Ward** » Tue Dec 13, 2022 12:20 am

enuff_zed wrote: ↑Mon Dec 12, 2022 5:39 pm Do you think GM5 or the Light Control Module?
GM5 is about £40 to get repaired.
LCM can easily be swapped and will work.................... you either live with a tamper dot on the dash or get someone to code it.

I would sooner bypass it all and eliminate anything that could and will eventually go pear shaped.

In order for me to activate the central locking I have to turn the car off and then wait 3 to 5 mins to activate it with the key fob. The lights are hit and miss, sometimes they will come on and stay on all night, other times they come on and 2 mins later go off completely or just simply refuse to come on. When they are on there are no lights on the dash to say they are on, not even main beam indication. No indicator lights, no fog light indication lights on the clocks. Doors always open signal even when closed. No indicator flashes when arming or disarming the alarm plus central locking.

I had the same problem with a Land Rover Freelander and ended up completely re-wiring the entire system so it was virtually fail proof. If something stopped working it ended up as it was just a fuse needed replacing, not a complete module.

Chris_D · Post by **Chris_D** » Tue Dec 13, 2022 10:08 am

You haven't confirmed that you have checked all the ground points yet. The intermittent nature makes it sound like this could be the issue.
find and disconnect, clean and reconnect all the grounding points before you start faffing around with old school rocker switches, which may turn out to be more of a headache to install rather than doing a root cause analysis on your existing problem.

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