Slow window fix using relays

[RUSSELLM]

I’m still not happy with my pax window. With the door open, when the window goes up, I can see the voltage dropping to around 9.5v. The window goes up properly now, but I can see it struggling at the top, and I’d like it perfect now I’ve got the card off.

I’ve greased the motor and mechanism, changed the inline connector in the door and the one at the lower A post.

I suspect the motor’s tired, and the Door Module can’t supply the current required.

Ideally, I’d like to buy and try a new motor, but TVR parts are out of stock.

I powered the motor directly from the battery, and it flies up. My conclusion being the motor will work perfectly well, just not with the module

So.....

I’ve done a little diagram using One of the Two output wires, from the module.

The output wire on the module sends a positive or a negative, depending on which way you want the window to go.

Looks like it can be done with Two double pole relays, situated next to the door module.

My question, as I haven’t tried it yet.... How does it look ? What have I done wrong ? Can it be made simpler ?



Edit.... I’m relying on One of those outputs from the door module, being volt free. Which I haven’t tested yet

Edited by RUSSELLM on Friday 29th May 21:09

[RUSSELLM]

Cheers, but I don’t think that’ll work in the Cerb. The ‘Open‘ and ‘Close‘ on that vehicle, I presume is a 3 position rocker switch.

On the cerbera, the motor has 2 wires, that go back to the door module.

It sends a positive down terminal 1 and a ground down terminal 2, to make the window go up.

And reverses the signals, to make the window go down.

I need to check tomorrow, to see what’s on those two outputs, whilst there’s no command.

[RUSSELLM]

Penelope Stopit said:

If all is good

The motor would be disconnected from the module and connected across the 2 relays

The module terminals 1 and 2 cables would be connected to the relay coils

Cheers Penelope That’s better than my way, and and it’s going to be easier to find a 10A SP relay, than a DP version.

One observation, the controller appears to have Two 20A separately fused ignition feeds for the windows. They’ve used 1.5mm cable, presumably thin wall.

However, they’ve used a single ground wire, also 1.5mm. I half expected to find something slightly bigger there.

I’ll get some relays ordered.

[RUSSELLM]

Byker28i said:

Is it just that the motor is tired,worn brushes, dirty commutator?

Definitely one of the factors. Plus a tired mechanism. Less than perfect rubber/felt on the runners, incorrect door seals etc.

I’ll get a new motor as soon as they get one in stock.

Only problem I see, is that the door controller can probably switch 5A quite easily. Even though they’ve used 21A cable protected by a 20A fuse.

When everything on that door is replaced, I’ve no doubt it draws less than 5A, and everything works fine, as it drives out the factory.

The problem arises, when you dare to not grease the motor/mechanism on a daily basis. Or if you take the car out of a climate controlled environment, eg outside, and nature takes it’s course. All of a sudden, that system needs to pull 6A to close the window, and that door module can’t do it

[RUSSELLM]

It’s a job for next weekend now

I was hoping to put the relays next to the door controller, but there’s too much volt drop along the existing wires. So if I fit the relays, they’re going next to the HVAC module.

That said, anyone who’s got slow windows would probably be happy with this....

https://youtu.be/Lbk7Gy5rKf0

That’s with the windows fully down to start with, then setting the alarm. I couldn’t get that to move an inch, from that position originally. It’s had the mechanism and motor lubricated, and the inline connectors replaced, to get it working like that.

Driver’s side looks a bit rough now, in comparison

[RUSSELLM]

That passenger side was as good as seized, in the fully down position

[RUSSELLM]

Rather than disturb the door grommets, I’m going to put the relays above the front passenger’s knees, near the other modules.

There’s a grommet up there, that currently has the rear fuse box 12v coming through it, so I’ll was going to put my new 12v through there, from the battery.

I could do the same with the 0v, but there’s a 17mm bolt up there for the roll cage, that has a great ground on it, so that’s been utilised

Edit... Just below that, you’ve got the Three inline connectors for the door. I’ve already took the Two wires for the motor out of there, and they’re now on their own new connector.

I suppose an added advantage of using the relays, is that it takes another load off that door controller. You’d like to think a seized motor would take out the supply fuse to the controller, but I’d put my money on the controller burning out first

Edited by RUSSELLM on Sunday 31st May 14:31

[RUSSELLM]

Finally got round to sticking the relays in today. I haven’t tried the silicone spray trick yet, however, I don’t think there’s any need to.

I’ve replaced the inline connectors at the door, and used the same connectors for the relay fix, so I can switch back to conventional in a few seconds, if need be.

I wanted to site the relays by the door/window module in the boot, but a quick preliminary test, leads me to think the existing wiring from boot to doors, can’t carry the load. I suspect it’s under rated for a tired motor or the 24 year old cable is breaking down

Relays are by the HVAC module, and went through the grommet for a new positive and ground feed.

Little video with and without relays, excuse the bit n the middle where I switched connectors ....

https://youtu.be/NWLsvd6idIo

From the outside, on an alarm set....

https://youtu.be/KrHV9Rvtv5w

[RUSSELLM]

Thanks Penelope, used your diagram too

[RUSSELLM]

Byker28i said:

Was there any difference in speed in the before and after, difficult to see, but they are certainly quick either way.

Before the relay wiring, is that just lubrication and new connectors? Might have to change mine out. Which connectors did you use?

Edited by Byker28i on Monday 20th July 08:53

Yes, it was seized in the lower position, and barely worked when you helped it.

I sprayed some WD40 at the motor and mechanism, then smeared the mechanism with white grease.

I replaced the 2 pin connector in the door.

The lower A post has the 2 wires on 2 different connectors, so I’ve put them in their own new connector.

So that gets the window working as seen at the start of the video, with a little struggle at the top and 2v drop.

The relay fix at the front of the car, eliminates that.

That window’s quicker than my BMW’s now

[RUSSELLM]

Byker28i said:

Ta, just wondering if to get new pins, or just replace the whole connector, but I'm worried what the state of the wire might be for reconnecting. The voltage drop measuring is a good idea, I might try that

They haven’t used any weatherproof connectors in the door, so I’d replace the connectors, rather than the pins. Plus the exposed copper on the cables, will appreciate getting cut back

There’s loads of slack harness in there.

[RUSSELLM]

Byker28i said:

Anyone had this done? Interesting they talk about voltage drops

Not me. A couple of things from their site though, they mention none standard relays... I haven’t seen any of them in my car. The window module as an example, has a timer in it.... If they want to replicate that, like a modern car, it’ll be a purpose built Body Control Module rather than a fuse box. Unless they’re messing about with timer module etc.


But having seen what happened when I tried that window fix from the rear of the car and barely seeing an improvement, I think I’d be rewiring the car, before looking at a new fuse box

Has anyone followed the battery negative lead yet, to see where it goes ? As mine has a horrible kink in it, so I’d like to replace that.

I’ll have to check the supply at my headlights, as they’ve never been great. They’ve been replaced recently, but I haven’t really used it much in the dark, to see how effective the new reflectors are.

I’ve got another door to do first though, then I’m going to get the hot and cold fans HVAC blowing a bit better.

Edited by RUSSELLM on Monday 20th July 16:14

[RUSSELLM]

jong1e said:

i recently added a new 35mm earth lead from my battery directly to the earth terminal in the boot my windows now are brilliant

I think that’s a good shout.

When I was messing about with my car the other day, I ran a temporary ground to the cold and hot air fans, and got a 10% fan speed improvement

[RUSSELLM]

I ran a temporary 12v and 0v to the rear of my car, but found that the existing wiring from window module to the lower A post, couldn’t carry the load.

I suspect the cabin harness is gradually breaking down.

[RUSSELLM]

They haven’t used any weatherproof connectors in the doors, so they’ll all fail eventually. The exposed copper on the pins being the first item to get attacked. Telltale sign for me, was the door exit button illumination getting dimmer. If you think how minute that load is, then consider the wiring can no longer sustain the load, then you know your window motors have no chance

I did the same with the A post connectors. The window’s on it’s own 2 pin connector. And I replaced the rest of those connectors. Did the same in the door too. Separated the mirror, door switch, windows etc... Should make future fault finding a bit easier.