Sun roof problems. 86 944

[Lance924]

I have been trying to find the fault on my sunroof(86 944).
I have followed all the checks on Clark's garage and still no joy.
When trying to operate the roof, you can hear the relays in the boot operating but the motor will not turn.
I have checked the micro switch at the front and that is working fine as well.
The output voltages onvthe switch are fine, the only thing i can find that is not the same as the instructions on Clark's/G is the voltage at pin A on the main relay socket. With ignition on it reads at about 7v not 12v. All other checks read as they should.
Can anybody shed some light on what the problem might be please.

Cheers

[Lance924]

I forgot to add that i have also checked the motor on its own and she spins up fine.
To rule out one thing or another i have also replaced the whole motor assembly to an 87 ver but still the same problem is there.I have also checked the motor on the new mechanism and it is fine also????????????????

[jmd_forest]

Use a long wire and jumper 12V to Pin A directly from the battery and see if it works then. If so, something in the pin A line is corroded/shorted and killing the voltage needed to turn the motor. Assuming this is the case, track down the short/corrosion in the line and fix it.

jmd_forest

[Lance924]

Originally Posted by jmd_forest

Use a long wire and jumper 12V to Pin A directly from the battery and see if it works then. If so, something in the pin A line is corroded/shorted and killing the voltage needed to turn the motor. Assuming this is the case, track down the short/corrosion in the line and fix it.

jmd_forest

Thanks for the reply,i will give that a try in the morning as its alittle dark here at the moment,12.20am.
i will post back with the findings,hopefully happy saying she works.

[Lance924]

Update.

I have tried putting a 12v feed to point A on te relay socket, but results are just the same.
You can here the direction relays operating in the rear of the car,also pressing the micro switch above the front window switches the direction relays as they should. But still will not operate the motor.
As i the first post the output voltages to the console switch are also fine.
?????????????????????????:

[jmd_forest]

I went through this crap last year so my memory is a little fuzzy, so please bear with me bear with me. Pry the plastic caps off the relays and work the relay with your finger. IIRC correctly, one relay is up, the other is down. This will let you know you are getting the correct voltage to the motor that it needs to run.

The wiring diagram for this thing is a real Rube Goldberg but sometimes it comes down to tracing through the wiring diagram and eliminating components one by one.

Oh, just remembered. The microswitch in the front, between the sunvisors must be activated for the motor to work in one direction (but the motor will work in the other direction just fine when the switch is ot activated). I found this out while troubleshooting the electrics with the sunroof out of the car.

jmd_forest

[Lance924]

Originally Posted by jmd_forest

I went through this crap last year so my memory is a little fuzzy, so please bear with me bear with me. Pry the plastic caps off the relays and work the relay with your finger. IIRC correctly, one relay is up, the other is down. This will let you know you are getting the correct voltage to the motor that it needs to run.

The wiring diagram for this thing is a real Rube Goldberg but sometimes it comes down to tracing through the wiring diagram and eliminating components one by one.

Oh, just remembered. The microswitch in the front, between the sunvisors must be activated for the motor to work in one direction (but the motor will work in the other direction just fine when the switch is ot activated). I found this out while troubleshooting the electrics with the sunroof out of the car.

jmd_forest

Update time.

I took the covers of the relays and then tried them by hand. And nothing lol.
Tried tried the switch again and both relays operate but not the motor.
I then ran a wire from 12v to the two red 12v wires that feeds the relay sockets.
Turned the key ,pressed the switch and the roof raised.(Just as the clouds came over and started to rain).But at least the roof operates. So conclusion is there is a fault with the feed to the motor but this is something that is not covered in Clark's/G checks. I'm going to trace the wire back to see if i can find any breaks and then just replace.
I just wanted to say thank you for your thoughts and ideas on this one as they have helped finding the fault.
Cheers



Just got myself a set of teardrop mirrors so going to have a play with those in the morning!!!

[jmd_forest]

You might try checking the fuse. Sometimes its the simple stuff.

jmd_forest

[Lance924]

Originally Posted by jmd_forest

You might try checking the fuse. Sometimes its the simple stuff.

jmd_forest

I wish it was one of the simple ones,I did check the fuses , 1 and 8 i think they were and both were fine.