The boot courtesy lights in my 2005 Elegance estate have stopped working.

 

It always shows correctly on the maxidot, whether open or closed. I also double checked with vcds and that shows the boot open and closing correctly.

 

I've checked both bulbs and they are fine. 

 

Testing the contacts on the bulb connector with the boot open shows only 1.3v on either side. This instantly drops down to 0 when the latch is manually activated.

 

Where is a good place to start looking? I assume the cable runs down the inside behind where the cd changer is?

 

The inside of the boot has always been dry and my rear washers works fine.

Edited 25 November, 20196 yr by softscoop

Forgive me if I'm talking egg-sucking here but did you check the voltage across the bulbholder contacts or from contact to earth?

 

If across the contacts you might have a poor earth connection downstream from the bulbholders.  I'd have to recheck mine but I believe the earth connection is copied from one side to the other (from left to right) and not to separate left/right earth points.

It was on the contacts in the back of the black connector - so I was measuring exactly the voltage the bulbs are getting.

 

I'm guessing  a poor earth is a possibility, but where is the connection actually earthed?

 

It was the same on both sides. 

7 minutes ago, softscoop said:

where is the connection actually earthed

 

There's a common earth point in the boot area but neither my car nor my manuals are here right now so I'll have to investigate later and get back to you.

 

In the meantime you can verify the earth problem by checking the voltage between the feed contact and any handy earth point on the car.

 

Just in case, check the bulb failure indicator isn't showing on the dash as if it is the relevant control module will have either disconnected or reduced the feed side.

 

I didn't think those lights were monitored?

 

There's no light out warning and nothing showing on vcds either

6 minutes ago, softscoop said:

I didn't think those lights were monitored?

 

Fair point; I assumed, and we all know how dangerous _that_ can be

 

I'll try the resistance to the bodywork from the pins.

This wiring harness diagram might help with visualisation for now; items 31 are the boot light connectors.  I can't identify the earth connection point yet but you were right to suggest the wiring goes up the left hand side passed the CD player.

 

Ok so I've measured again.

 

Resistance between the light connector and the outer side of the boot 12v socket was infinite. Tested on several bare bits of metal I could find and they were all the same.

 

Tested voltage between the positive pin and the bodywork gave 12v.

 

Time to find the earth.

Now I'm re-united with my manual I can offer the following:

 

1) the common earth for the boot lights is E6 which is in the left hand luggage compartment. FYI E7 is also reported as in the same compartment; all earth points are created equal but see note below about broken wiring.

 

2) the wiring diagram shows separate earth lines (white/blue) running from each light and splitting, one lead to to E7 and the other to the convenience control unit (delayed off?).

 

3) the fact that both lights are FU'd suggests a problem at E7 as the wiring diagram does not indicate an earlier joint.  Not sure how the CCU plays here.

 

4) the problem could be broken conductors within the wiring. Clean and refit the E7 point first then if necessary check for continuity on both earth wires.

 

5) FYI E7 seems to be the earth point of choice for the rear lights also - lots of Brown wires.

 

If the above doesn't make sense I can scan and send you the wiring diagrams if they would help.

 

 

 

Edited 27 November, 20196 yr by StickyMicky
typo

A scan of of the wiring diagram would be really handy.

It would really help visualise what I'm looking for.

Well I cheated.

 

I stripped some of the cloth tape surrounding the wires next to the boot light and used a scotch lock connector to add a bit of extra wire with a connector on the end to the blue/white earth wire.

I just connected that to one of the bolts for the rear lights -and hey presto they now work fine.

Well I spoke too soon.

 

They are on whenever the car is unlocked, even when driving.

I can't imagine they are switched earth instead of live?

 

At least they go off when I lock the car, so my battery hopefully won't go flat.

Watching this topic as we have the same issue. 

Putting in your extra Earth wire could be bypassing a failed microswitch in the tailgate lock, thus keeping the lights on all the time when driving. I know the maxidot display shows correctly when the boot lid is opened and closed but that may be using a second contact. The diagram (may be earlier) I have shows the lights being switched by the boot switch connecting to ground via a wire to E7.

 

Take out the boot switch and check all wires and operation of all microswitch contacts. If more than one microswitch, check that it is not just a matter of adjustment of the boot lock position to ensure that both microswitches operate when boot closed.

Resurrecting this post but I have the same problem. Could someone let me know where the boot switch is (on an estate)?

 

Many thanks.

13 hours ago, Hairsy said:

Resurrecting this post but I have the same problem. Could someone let me know where the boot switch is (on an estate)?

 

Many thanks.

 

It says it in my post immediately above yours.

It is in the tail gate lock. Remove the two screws on the sill and lift the lock upwards so you can disconnect the wiring connector. May be different on facelift models.