Ian964CAB

Hi Guys,

I am in trouble again! My rear spoiler will not work either whilst driving or by using the switch. When using the switch all you hear is a click under the O/S/F seat.

I have checked the fuse, also the continuity between the switch and module under the seat and through to the engine bay and finally to the spoiler. I know the motor is working as I can run power to it and make it work.

With all the wiring intact, a new module and knowing the fuse, switch and motor are all working I cannot even begin to imagine what the problem is

Does anyone have a wiring diagram, know what each pin on the module should read or have any idea what the problem could be.

All help or ideas greatfully appreciated!!!!

Ian

ddubois

My guess would be the microswitches that tell the control unit when the spoiler is retracted or extended. Don't know your year, but on my 91 the extended pinout on the CU is pin 9, and the retracted is pin 10. The switches close a ground circuit to the controller.
If it's a case where the spoiler won't extend, then likely the extended switch is stuck closed telling the CCU it's up and to turn off the motor, or in your case don't turn on and raise the spoiler. Or it could be the retracted switch isn't closing and the CU is programmed to do nothing when it gets conflicting input such as both switches open or closed at the same time. I've seen this kind of logic and response to ground switches in the alarm/central locking system.

Ian964CAB

Hi Doug,

The model year is 1990. The module P/N is 964.618.212.00 I do not know if this is the same as yours.

Would there be a way to check the micro switches affected this? I have manually wound the spoiler up and it will not close either.

Ian

Ian964CAB

Hi Doug,

Also should pin 9 be 12v positive when extending? and pin 10 12v positive when closing, or is it earth switched?

Ian

ddubois

The 90 schematic shows pins 9 and 10 the same as what I described for my 91. They are both ground (or earth on your side of the pond) switches. Check the microswitches at the spoiler to make sure they are contacting correctly.

boxsey911

It could be that the mechanism has come apart. Mine did and I've heard of a number of others that have.

Take off the plastic cover over the mechanism on the left hand side to have a look (this assumes you have one - mine didn't). Put a towel underneath first to catch any bolts that drop. The mech is attached to the lid by 3 allen bolts. These can work loose.

Ian964CAB

All sorted! it seems that there must be a poor contact from the fuse box to the module. I have a new power feed and it is now working.

Thanks again all you guys for your input, I hope I may be able to read a thread and come up with an answer that can help someone soon.

Ian

J Diddy

just had the same issue on my 964 c2, very helpful post, cheers

brogich

Could someone tell me the correct way for the rear spoiler to operate. It seems to me that sometimes its up - sometimes its down. When the car is off and in park should it always be in the closed position?

Brian

Streetfighter

When the car accelerates over 45mph I believe the rear fin will engage and come up. Once the car drops speed below 45 mph the fin will retract. It doesn't do it right away, but after a minute or two below that speed it will stay flush. When your putting around town at 30 mph it will not come up. When you park it should be down. Some people will switch it so that it is up all the time. There is a manual switch to do that on your center console.