Weird Electrical Issue - Help Required Please (2 Viewers)

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Now if I leave my car overnight and press the remote in the morning there is not enough power in the central locking to open the doors, so I have to open the drivers door with the key.

What about the rear door, Spud? In the morning when you see this symptom of not having enough power in the central locking to open the doors remotely, does the rear door still open but none of the other 4 front ones?
 
Sorry I made a meal of that explanation.
The main switch does all the work for the 4 passenger doors, you can trace that path easily with your finger. The normal state of the switch is how it's drawn so when the lock side is pushed that contact closes and the return path is back through the switch through the unlock side to the negative.

The 2 relays are for the tailgate and it's drawn a bit strange because I don't know why they wouldn't just use a double pole relay (judging by the labels they may have).
Any way that's where the selective current path is, again if you trace it with your finger you can see the relay is operated by the main switch which brings it's contact up which is the positive for the coil for the back door. Depending on which way the switch calls the relay dictates which back door contact is picked thus creating the lock/unlock function of the back door.
I'm really not sure why they didn't just extend the circuit for the back door or use the back door circuit for all the doors because the later would certainly help the door lock behaviour.
 
Sorry I made a meal of that explanation.
The main switch does all the work for the 4 passenger doors, you can trace that path easily with your finger. The normal state of the switch is how it's drawn so when the lock side is pushed that contact closes and the return path is back through the switch through the unlock side to the negative.

The 2 relays are for the tailgate and it's drawn a bit strange because I don't know why they wouldn't just use a double pole relay (judging by the labels they may have).
Any way that's where the selective current path is, again if you trace it with your finger you can see the relay is operated by the main switch which brings it's contact up which is the positive for the coil for the back door. Depending on which way the switch calls the relay dictates which back door contact is picked thus creating the lock/unlock function of the back door.
I'm really not sure why they didn't just extend the circuit for the back door or use the back door circuit for all the doors because the later would certainly help the door lock behaviour.

Yeah, that's what I'm thinking too, Crick...

I read it operating how you just explained it.

Which would mean that if there is some drain through the Door Look system, it's probably gonna be through the switch. Strange that they didn't use relays with the 4 main doors but only on the rear door...I wonder if that switch ends up being the problem if there might be a clever way to wire in 2 (for the lot of em) or 4 (individually) relays into the 4 door solenoids...but not sure that would protect the switch from leaking to see ground since , as you point out, the circuit grounds back through the switch anyhow, so if the short is internal to the switch, it's not going to matter how the solenoids are set up...
 
Hi guys

Firstly I don't have the tail gate central locked, the actuator was stuffed in the doner vehicle.

I checked the battery last night 12.45, I then checked it this morning 12.44 so that's all good.

I had a quick look in the passengers kick board, couldn't see any earth wires, are they supposed to be there or under the A pillar itself.

I spoke to my mechanic today and he said to get under the car and run an earth from the gearbox to the body and try that.
 
You can almost guarantee it's gonna be a dodgy earth somewhere.
If the strap doesn't work try having another look around the earth you used for the alarm and central locking, maybe run a new test lead to the neg battery to see if that improves things when it's not playing nicely.
 
I had a quick look in the passengers kick board, couldn't see any earth wires, are they supposed to be there or under the A pillar itself.

Not sure, Spud. The only info I ran across identified that common ground as "under left front pillar"...

Can you leave the vehicle unlocked overnight? If so, I wonder if you can test the Door Lock circuit by removing the "Door" fuse (make sure doors are unlocked or a window down, or rear door is unlocked(able)) when you park for the evening, and then in the morning, if you reinstall the "Door" fuse, do you still see the same symptoms?

EDIT: Actually, I wonder if the front doors will work with power even with the "Door" fuse removed, since (if I'm reading the wiring diagram correctly) that fuse only affects the rear door circuit...the front doors are protected by the circuit breaker...
See if the power locks on the front doors work without the "Door" fuse installed.

In fact, you mentioned that the power to the rear door is buggered and doesn't work on the power command...are the relays and solenoid still installed? Could the failed rear door relay/solenoid be causing these symptoms?
If removing the "Door" fuse relieves the symptoms that happen first thing in the morning, and the power doors on the front doors still work with the "Door" fuse removed, then you have to suspect that the rear door solenoid/relays/ground is the culprit...
 
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You can almost guarantee it's gonna be a dodgy earth somewhere.
If the strap doesn't work try having another look around the earth you used for the alarm and central locking, maybe run a new test lead to the neg battery to see if that improves things when it's not playing nicely.
Thanks mate, yes that is the next option
 
Not sure, Spud. The only info I ran across identified that common ground as "under left front pillar"...

Can you leave the vehicle unlocked overnight? If so, I wonder if you can test the Door Lock circuit by removing the "Door" fuse (make sure doors are unlocked or a window down, or rear door is unlocked(able)) when you park for the evening, and then in the morning, if you reinstall the "Door" fuse, do you still see the same symptoms?

EDIT: Actually, I wonder if the front doors will work with power even with the "Door" fuse removed, since (if I'm reading the wiring diagram correctly) that fuse only affects the rear door circuit...the front doors are protected by the circuit breaker...
See if the power locks on the front doors work without the "Door" fuse installed.

In fact, you mentioned that the power to the rear door is buggered and doesn't work on the power command...are the relays and solenoid still installed? Could the failed rear door relay/solenoid be causing these symptoms?
If removing the "Door" fuse relieves the symptoms that happen first thing in the morning, and the power doors on the front doors still work with the "Door" fuse removed, then you have to suspect that the rear door solenoid/relays/ground is the culprit...
All I can say is when are you coming to Western Australia for a holiday, we need to get together.

Thanks for all the hard work you have done. I don't have the rear actuator connected or even in the vehicle, it was another project to find one and put it in.

So I'm thinking the earths might be in the pillar itself, I'll have a look.

The biggest pain is finding time to work on her ATM so busy at work.
 
All I can say is when are you coming to Western Australia for a holiday, we need to get together.

Thanks for all the hard work you have done. I don't have the rear actuator connected or even in the vehicle, it was another project to find one and put it in.

So I'm thinking the earths might be in the pillar itself, I'll have a look.

The biggest pain is finding time to work on her ATM so busy at work.

No worries, Spud! Just trying to add to the conversation...

Yeah, then I'd give removing the "Door" fuse and removing the two relays in the rear PS (Australian PS side) quarter panel a try and see if the problem goes away...

...if not, then the only other thing to blame (besides that common ground) on the Power Door Lock circuit would be the switch itself (remember, it ground back through the switch as Crick and I figured out above) or the circuit breaker (which can be reset, so easy enough to rule that out, too)...

After that, I'm with Crick and the mechanic...sounds like a dodgy ground in the charging system...
 

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