Ford and Volkswagen MPV Forums

Large MPVs -- Ford Galaxy / VW Sharan / SEAT Alhambra: => Ford Galaxy / VW Sharan / SEAT Alhambra => Topic started by: alexdukes on July 01, 2020, 03:50:17 PM

Title: Problem with Map Reading Lights and Vanity Mirrors
Post by: alexdukes on July 01, 2020, 03:50:17 PM
Hi Everyone,

I have just recently bought a Galaxy 1.9TDI Ghia 2005.

It has a strange issue, the cabin lights are working fine when the doors open and close and the 10 minute timer works aswell, turning them off if a door has been left open. The internal lights also turn off when the alarm is set etc.

The problem however is that none of the map reading lights, vanity mirror lights or the rear book reading lights work when you move any of the switches?

I have tested the bulbs and they all are fine, I think I have tested all of the correct fuses swell and they seem to be OK.

Have you got any ideas how to fix this?

I look forward to your help!

Thanks
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: SirDavidAlhambra on July 01, 2020, 07:34:34 PM
Hello my friend and congratulations on the purchase of your Ford Galaxy 1.9 diesel, it is truly one of the finest cars money can buy. Comfort, power and space - not to mention safety.

Could the prob with the lights be a broken power cable or something maybe, could u put a multimeter on it and check
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: SirDavidAlhambra on July 01, 2020, 07:36:13 PM
Also I forgot to mention the fuel economy, truly amazing for a vehicle that size.

Iím so happy with my Alhamb
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: alexdukes on July 01, 2020, 10:06:12 PM
Thanks for the comments but I don't think it can a loose cable as they work the rest of the time?
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: regw on July 01, 2020, 10:31:38 PM
My money's on a bad ground
a quick meter test will confirm/deny this
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: Mirez on July 02, 2020, 10:33:53 AM
The important one to check is the main light, the one at the front with dome light and map lights in one. If the dome light works here (which it sounds like it is) but the map light doesn't then its the ground 'supply' for lighting circuit two. There is a permanent 12V to the lights and its the ground that is switched, which in real terms means its likely the BCM has an issue rather then any fuse / relay.

I have seen this before a few times and in some cases its resolved by power cycling the BCM (yes, the old turn it off and on again!). Realistically, the only way to do this is to disconnect the battery, wait 5/10 minutes and then reconnect so make sure you have your radio code to hand first.
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: alexdukes on July 02, 2020, 12:55:42 PM
Not sure what I am supposed to be getting, there are 4 wires into the front dome light, I only seem to be getting 12v from 2 of the cables.

Does anyone have a wiring diagram? Or a picture labled up with what should be what??

Turning it off and on again sadly didn't work!
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: alexdukes on July 05, 2020, 01:54:12 PM
** UPDATE **

So I found a BCM on Ebay and decided to go down the route of trying to swap that out to see if that would make a difference.

Sadly no change

Whilst I was there, I dropped the front dome light again and measured the voltage across the map reading bulb terminals, I was getting 12v????  I then went to get a new bulb and put it in the holder thinking that it would all be OK, but still nothing....

Getting REALLY confused now, is there something I am missing??
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: alexdukes on July 05, 2020, 02:41:34 PM
SOLVED

So, my silly oversight, I didn't do a great job of checking the grounding at the front dome light, the previous owner had obviously had the front windscreen replaced at some point and the ground wire was touching the grounding point but not bolted down.

Bolted it down and now all fixed!

Anyone need a BCM??
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: regw on July 05, 2020, 03:04:01 PM
Good
lesson learnt
we've all dived in swapping stuff before proper testing
then we learn testing before guessing is often quicker and cheaper

What is a BCM anyway
i'll guess a controller/relay board some sort
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: Chrispb on July 05, 2020, 03:57:43 PM
BCM= Body Control Module
Title: Re: Problem with Map Reading Lights and Vanity Mirrors
Post by: brianh on July 05, 2020, 04:17:59 PM
SOLVED

So, my silly oversight, I didn't do a great job of checking the grounding at the front dome light, the previous owner had obviously had the front windscreen replaced at some point and the ground wire was touching the grounding point but not bolted down.

Bolted it down and now all fixed!

Anyone need a BCM??

Good job at posting the solution for anyone else who has this problem, thanks!