Interior lights

[jonthevicar]

My Mgf s interior lights appear to have an intermittent fault.
Sometimes they work and sometimes not.

I assume this is due to a switch somewhere in the door, or could it be a relay sticking?

Has anyone else had simillar issues?

Thanks

Jon

[Mykel]

Hi Jon,

the switches are actually incorporated into the door lock assemblies. Yet they do not control the interior lights directly, but via the multi function ECU. Current also runs across some taps and headers buried deep down somewhere .

So to get down a bit more to the core it would help to know if this intermittent failure
- affects all four lamps (foot well lh&rh, the two in the rear view mirror) at the same time
- occurs only when opening one specific door or on both
- looks like some loose contact, ie the lights go off and on again for no obvious reason

Then it might be easier to track the faulty bits.

Cheers
Mykel

[jonthevicar]

Hi Mykel

Thanks for the reply.

The problem when it appears affects all 4 lights.
They either all work or all don't

Jon

[Mykel]

Well Jon,

so the plot thickens. Might be one of the switches in the door mechanisms, or the wires in the loom going into the doors. I would actually rule out the multi-function ECU itself or the fixed cables and header joints in the first place. These tend to rather work or not, normally not producing intermittent failure.

You should now check which door doesn't trigger the lights when opened.

Then we can narrow the possible cause a little more.

Cheers
Mykel

[Rob Bell]

Does this intermittent fault effect both doors, or just the Driver's side?

My suspicions would centre on the wiring loom to the door lock, or to the door lock connector. What vintage is your MGF? Chances are the problem may lie with the external connector.



I suspect that you'll have the later version, as this changed over some time in 1996... and it is the loom that plugs into the two-pin socket that may be a cause of problems. Contact cleaner is your friend.

[newtomgf]

Hi, I have recently bought a 1999 mgf and am loving every minute of it so far. I have encountered a similar problem with the internal footwell lights and initially thought it was a dud bulb. So i bought replacements. After taking the old bulb out i found the metal end contact to the bulb was no longer soldered to the end of the bulb and simply replacing the bulb seemed to solve the problem. I hope this helps.

However i have now found a different problem where the backing to the light assembly seemed to be getting very hot and had started to warp and looks like it is melting. I have taken out the bulbs until i find a solution. Any suggestions would be much appreciated?

Thanks

James

[artful.codger]

Did you replace the bulbs with the correct rating? The interior footwell bulbs should be 5 watt. If your new ones are more than that they will be hotter with the obvious consequences.

BTW, welcome to the forum.

[jonthevicar]

Right

This morning, no interior lights on either side. Also if I leave the lights on and open the door no warning buzzer.

However after my 35 mile drive to work interior lights work if the drivers door is opened , but not the passenger door.

Over to you guys

Jon

[Mykel]

Hi Jon,

definitely the loom and/or the switches. I'm afraid you will have to take the door panels off and have a close look at the wiring.

You can check the switches when you disconnect the wires and short the purple/white (driver's side) or purple/grey wire against the black one. On the passenger's door these are in the same connector, on the driver's side the black one sits in the extra 2-pin connector - don't mix it up with the black/orange one!

If this works, then the wiring is okay.
As Rob said, drain the connectors with contact cleaner and see if there's any improvement. If so, lucky you are! Otherwise the switches themselves will be the problem. AFAIK this means that you'd have to change the locks.

If shorting the wires doesn't work as well, check for broken wires, especially in the tube that runs from the body to the doors.

HTH
Mykel

[jonthevicar]

Thanks Mykel

I will investigate further.
Rob are your door card removal instructions the same for a 2001 model?

Jon

[Rob Bell]

Yes, they're exactly the same Jon

[jonthevicar]

I haven't taken the door apart but have found that if the lights don't come on, a tap on the door next to the lock wakes up the microswitch!

[Mykel]

Well Jon,

this may be cheap but labour-intensive I'd suggest to take the little darlings out, dismember them, give everything a good clean & grease and reassemble. Bit fiddly I'm afraid, but that's what we MG enthusiasts love about our cars, isn't it?

Cheers
Mykel