Door solenoids

Door solenoids



Original Poster:

763 posts

188 months

Monday 19th October
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I struggled to find any detailed account of how to change the door solenoid, and as a job it is a pain the the a**e having just done it (three times actually until I had it right), so to help any other poor sod who has to do it, read on. The usual disclaimers apply - this is how I did it and avoids the mistakes I made which mean't I did it three times and now have a bad back. If you try this, it is at your own risk, and particularly with the electrical connection. This was on a Tuscan Mk1, your car may vary.

1) Call your local TVR specialist and see whether they will do it for you. If they will, let them get on with it. Really.
2) If they can't/won't/laugh hysterically then:

- Lower the window fully. Open the door. Tie/cable tie a thick rag around the door pin so that it won't close. Get a good strong torch.
- Remove the escutcheon plate on the lock by removing three small screws. You will see a microswitch this governs the windows opening and closing - tape the arm of the switch up to the switch to avoid it getting damaged.
- Push the seat as far forwards as it will go, and then fold the seatback forwards as far as it will go. You will have to do this job by working around the corner, or removing the rear screen and sitting on the parcel shelf.
- Remove the allen bolt at the base of the seat belt cover panel. Carefully pull the bottom outwards making sure you don't damage it (it will need a little twist to clear the seat, and then lift the front edge up to release it at the top (it just has a lip that seats below the side window)
- You will now be able to see inside the B pillar with aforementioned torch. The seat belt will be in the way and will continue to annoy you throughout the rest of this job.
- You will see a square metal "box", which is held in place by the two allen bolts coming from the striker plate on the other side of the B pillar. On the opposite side of the "box" are the solenoid and the emergency release cable. Inside the box (which you can't see) is the linkage from the striker plate to the solenoid/release cable.
- stuff loads of rags down the B pillar to block the hole. You will drop screws etc. There are entire tribes that ventured into that B pillar and have never been seen again, so any screws you drop are likely gone for good - they will however haunt you over every bump...........
- follow the electrical cables from the bottom of the solenoid to the connectors. Mine had 5 wires (two double connectors and a single), however only two will be connected - NOTE THE WIRE COLOURS on both sides of the connectors that are in use, then disconnect at the connector. This a good point to test the new one, either using the feed connector, or use wires and another 12V battery. If you have a voltmeter, you can measure across the feed connector when the button is pushed to prove you are getting a signal and the solenoid is at fault. If you aren't comfortable with electrics and the old connectors are not the same as the new ones, then stop now and seek help.
- Now remove the two allen bolts holding the striker plate. The box will now be loose-ish.
- twist the box gently until you can remove the two self tapping crosshead screws in the bottom extension to the box, that retain the solenoid. A stubby screwdriver is ideal for this, preferably magnetic. Be careful not to drop the screws. I found the best place for the torch is jammed behind the roll tube pointing down.
- At the top of the solenoid is a metal "hook" that extends up to the release lever. It bends at 90 degrees and passes through a plastic grommet with an integrated plastic G clip. Rotate the G clip off the Hook and pull it out of the grommet.
- the emergency release cable will be attached to the other side of the solenoid by a bracket with two more self tapping crosshead screws. Twist the cable gently to expose the screws and remove them.
- Remove the solenoid, noting which way it is orientated.

The solenoid is a plastic housing with wires, a gaitor and an eye at the end. This is important - it should have a spring within the bellows that ensures it is extended when not connected. If the bellows are compressed then you need to follow the step below, if they aren't then fill in a lottery ticket this week and proceed to the electrical connections.

From the old solenoid, push the gaitor up and away from the plastic housing and remove it over the eye and hook- DO NOT REMOVE THE "HOOK" YET.

With the bellows removed, you will see the spring. The spring is held in place with a C clip next to the eye. Compress the spring away from the C clip, which then slides sideways out of the unit, allowing the spring to be removed. Reverse the process on the new solenoid, ensuring the bellows are properly seated in their lips at both ends.

Now examine the electrical connectors. If they are not the same then splice in the old connector to the new solenoid wires MAKING SURE THAT THE RIGHT WIRES WILL BE CONNECTED FROM THE FEED CONNECTOR. I did this using insulated spade connectors between the old and new wires as I'd run out of heatshrink connectors. Test the new solenoid again by plugging it in loose. When the button is pushed the bellows should contract and then extend again as the spring takes over. If you keep your finger on the button this will repeat.

Finally, before re-assembly, put both the new and old solenoid side by side in the same orientation, and move the "hook" from the old eye to the new eye ensuring it has the same orientation.

You can now start reassembly.
Screw the emergency release cable back onto the side of the solenoid
Push the hook through the grommet and rotate the clip around to secure it.

Screw the solenoid to the lower extension to the box (all of this sounds easy - you will learn some new curses)
Put the bolts back through the striker plate and into the box - if you have the light in the B pillar recess it make this a lot easier to find the holes. Do not fully tighten them yet.
Ensure all of the electrical connection are in place.
Remove the tape from the microswitch.

To test, first push the button and see if you hear the solenoid fire. If so using a rod or screwdriver, push the lever in the centre of the striker plate towards the centre of the car, it should lock with a hole showing in the striker plate groove (the "hole" retains the door pin). you shouldn't now be able to move lever outwards - if not, adjust the striker plate and try again. Now pull outwards on the hole with a rod/screwdriver whilst pushing the button, it should release, Repeat but with the emergency release. DO NOT CLOSE THE DOOR UNTIL THIS TEST WORKS. I found that adjusting the striker plate can make a difference. Make sure that the microswitch works properly and opens and closes with the striker plate lever moving.

Remove the rags from the bottom of the B pillar and from the door pin. Put back the seatbelt cover. Lower the window fully.

Now test that the door opens on the button and with the emergency release. You may need to adjust the striker plate for perfection. Once complete put the escutcheon plate back.

This all sounds really complicated. It isn't but I've tried to be detailed so that the pitfalls are avoided. It is fiddly and awkward, and requires some patience the first time. Now that I've done it I could do it again fairly quickly, with only a little support from my psychiatrist afterwards

Edited by Konrod on Tuesday 20th October 07:59

Basil Brush

4,661 posts

223 months

Wednesday 21st October
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Nice write up. I had to replace the driver's one on mine but I think my brain must have blocked out the traumatic memories as I can't remember beyond removing the trim panel (and breaking the front edge as it had been glued on). The boot one is fun too!

so called

7,802 posts

169 months

Wednesday 21st October
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Have you replaced due to lack of 'Umphhh'?

My drivers side always needs at least two presses of the button!


Original Poster:

763 posts

188 months

Thursday 22nd October
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No, SC, It had been replaced about two years ago when in for a service for sluggishness. It just stopped working, no warning, confusingly just after I'd washed it which of course made me think that was the problem. I faffed around with the controllers first (swap left right etc.)scratchchin. Took the old solenoid apart once I'd fixed it (easier said than done as they are sealed) and the solder joint on the earth return wire inside had come away.

As a matter of interest, when it was sluggish a few years ago I took the controllers out and found loads of dry/poor joints where the plug pins attach to the daughterboard. Re-made all of those and it has removed any flakiness in the operation i.e. pushing the button and it doesn't work first time.

Richie C

551 posts

166 months

Friday 30th October
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I need to look at my passenger side. Putting it off as I've been in there before and I still have the scars.


Original Poster:

763 posts

188 months

Thursday 5th November
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Hi all. This may be of value to some of you. Having solved the driver's side problem, and successfully completed therapy, I moved over to the passenger side.

This has been bugging me. When you press the button, the solenoid fires but the door only goes to half catch. You have to press the button and pull the door to open it and it is very hit and miss.

The solenoid has been replaced, so I discounted that, and started by loosening the two lock bolts slightly, so that the pin would find the right seating. No difference.

I was resigned to stripping the lock and solenoid assembly, when I noticed that the door was catching the door surround edge trim. When I looked, the rear of the arm rest protrudes beyond the line of the door panel, and it was the same on both doors. On the driver's side the arm rest does not go past that edge trim into the car so isn't a problem, but on the passenger side it passes over the edge trim and when opening the door, it catches preventing the door opening fully. As both of my armrests are the same, it possible others will have this problem.

Fixing it was protracted. Remove door card, remove four bolts holding the armrest on, open out the holes in the door card so the armrest can be bolted on further forwards/up, grease window mechanism whilst I have access and apply silicone spray to the window channels. Re-rivet the rubber weather panel that was floating loose, and then re-assemble everything.

Hopefully that is the locks and doors done for a long time clap