Some may notice I also have a project thread for my X308, along with my other cars. But after some much needed body repairs/paintwork, my car has returned with three electrical faults that do not seem easy to diagnose. I wonder if those on this forum may have some ideas that might help?

So first of all, the car went in for this:

- Front bumper, 2x left side doors removed, bonnet removed.
- Both suspension strut towers ground back, rust removed.
- Repair panels welded to underside of both suspension strut towers.
- Painted inside arches, and on top of strut towers (would have needed looms to be moved out of the way, and some parts must have been released/removed).
- Painted front bumper, both front wings, bonnet, rear left hand side arch.

When the car went in, it worked perfectly, but when it came out it had the following electrical faults:

1) The boot will only open by the key; the buttons on the bootlid, dash, and fob do not open it.
2) The left hand side front indicator lamp does not work.
3) There is a warning on the dash pod that the coolant is low level, but the coolant level is actually fine.

I have done a bit of investigation already, but so far I have been unable to work out the cause of any of these issues. I am now wondering if it could be the battery, and whether I should remove the power, then charge the battery, to see if that helps.

Any ideas chaps?

 

The front indicator

So giving an idea of what I have done already....

I removed the front indicator lens, and then inspected the bulb. I used a multimeter on continuity, and the bulb seems good. I them removed a good (working) bulb from the rear light cluster, and tried that; no joy. So it seems it is not the bulb... that would be too easy!

I then measured the voltage at the bulb holder. When the hazards are switched on, the centre pin is permanent 12V to earth, and the side pin is continuously changing. My multimeter is too slow to see what to; but this makes it look like things are working, and I guessed it might be a switched negative.

Out of interest, I tried all the other lamps on the car, with the exception of the brake lights. Every other light seems to work fine.

I then found the page with the lamp in the X308 electrical guide, and realised the indicator goes to a common Earth point. So I am thinking I should be seeing a permanent 0V on the negative, and a switching positive.



So I am thinking I have a dodgy earth stud somewhere or a broken -ve cable for the lamp. My gut tells me is will be a wire broken, as surely a broken earth would take out more than just this one lamp.

I managed to get my hand in under the car, to feel around and find the bumper mounted connector. It seems to be plugged in OK, but I have not removed the undertrays to check for sure.

That (after checking the battery) is probably the next thing to do...

Any other ideas would be welcome!

 

The non-opening trunk

When the easy answers did not pan out for the front indicator lamp, I decided to look into the trunk not opening on the buttons. After all it is possible they are related I guess...

So I know the trunk can be opened manually using the key, but the buttons on the key fob, dash, and bootlid do not open it. The dash also propts "trunk open" permanently, even when the trunk it closed, so the car also thinks the trunk is open, even when it is not.

The oddest thing is I cannot see why the bodyshop would have needed to go near any of this...

Out of interest, both lamps inside the trunk work fine. I did not check if they go out when I close the trunk (not that I can see how to do that without trapping myself in the trunk...

I found the relevant page in the Jaguar electrical guide.



It seems to me that as the dashboard switch, boot mounted trunk release switch, and fob button are not commonly connected, it is more likely the solenoid is the problem. I suspected the earth point, but as this is shared with the fuel filler cap solenoid (which works fine), I would say I can rule that out. So am then thinking it could be the output from the security and locking control module to the solenoid.

But the thing that sticks out in my mind of particularly odd, is why there is a warning on the dashboard that the trunk it open. Why would a non-working solenoid cause a trunk switch issue??

Any ideas??

 

The coolant low level warning

I originally assumed I had obviously lost some coolant, and cursed the faithful Daimler. But when I got home and checked it, the level was fine. I even overfilled it to make sure.

Then I did a bit of reading, and realised the sensor is on the underside of the tank, and it would have to be very low to trigger the alarm.

I located the sensor, and all looked fine. The connector was firmly plugged in, and I could see no damage to the cable.

Then I took away the windscreen cowling, along with the under-bonnet covers, and realised the cable disappears where you cannot follow it...

I found the relevant page from the X308 electrical guide, and it appears the cables go to an earth stud, and the instrument pack (which I guess means looking behind the speedo pod.



I have not yet found the earth stud, which would be a good one to rule out.

Again... other than my current plan of action... any ideas?

 

Chris, you probably know I can't help much when it comes to actual work but for the interior trunk lights going out or staying on when the trunk is closed you could set your phone to video and place it in the trunk to see what it records when the trunk lid is opened/closed...

 

Good idea!

...that will save me shutting Aston in the trunk.

 

If it's been sitting at the paintshop then yes the battery will need a charge, they don't like a V drop.

While it's off you're performing a hard reset, so on reconnection see if the faults are still there.

I've had similar things happen, once from a jump start that blew a few fuses in the rear heel board boxes. Things like the seats didn't work and some lights.

On the indicator, I wonder if it's just disconnected, that wing would need to come off to complete the strut top welding.

Low coolant is the internal float sticking to the shaft it rides up and down on, use a finger to slide it up and down to clear any limescale.

Boot power could be either a wear related broken wire in the trunk lid loom, or fuse.

 

Some great ideas for me to look at there, I'm very grateful!

I have measured the battery voltage at 9.4V, so I put the battery on charge tonight. Will give that a go and see if it helps.



After that I'll take a look at that float switch, but the other two things I guess I'll have to chase through...