irishporsche

Hi,
This is my first (hopefully of many) posts here. I just bought my first Porsche, a RHD 1989 964 C4 and I am loving it.
Amongst a few other known problems, the spoiler is not working and I have read multiple excellent threads on the topic. I suspect the issue to be electrical and not mechanical but I cannot find the control unit for the spoiler. I have looked under the passenger side dash (central locking unit is there) and under the seats. Does anyone know if it is supposed to be under the driver or passenger seat and where specifically it is located? Does anyone have a picture of it in this location?

One obvious answer could be that the unit has been removed which would also explain my problem! I just want to figure out where to look.

Thanks in advance!
Keith

911URGE

Ive never gone looking for it but according to the US service manual its under the right seat. Part number is 964 618 142 00. Its a fairly small rectangular unit smaller than the cruise control module. Also under the right seat is the cruise control and possibly a radio booster. DME would be under the left seat.

Hope that helps.

BTW - Welcome to Rennlist. Lets see some pictures of this RHD 964 C4

speedcat

I have a LHD 1989 964 C4 and the spoiler unit is under the passenger seat.

911URGE

Correct, under passenger or right side seat on LHD cars. I dont know if Porsche reversed the units and wiring on RHD cars...but you never know. See if you can find the part number I stated above on any of the units and look for an empty plug on the wiring harness in this location.

boxsey911

Don't be too quick to assume it's not mechanical. It can be caused by the gear mech (on the left hand side) coming loose. This is obvious when you lift the engine lid if you've got no cover over the gear mech. It will have dropped off like mine did!

If you have the luxury of the cover still in place you will need to remove that first and have a look inside. But place something underneath first to catch any bolts that might drop.

ilko

Slightly OT: can you raise or lower a spoiler mechanically, or does it have to be moved electrically?

irishporsche

Thanks all. I have located the control unit finally! The next challenge is to remove it. It seems to be attached to the floor plate of the car. Looks like a single screw as I can slightly rotate it. Is there a trick to remove the entire unit or does the cable and electronic inside seperate from the housing? If so how?
I'm 6"4" and working on it upside down across the car so its a bit tricky!

I am getting some serious battery drain (empty in <1 day) also. From previous threads I suspect this is related to either the spoiler problem or heater.

While I was under the seat I also found a 2-pin electrical plug and socket which was disconnected. Anyone know what this is? The seat is option 387 sports seat, electric operation works fine. Perhaps it is seat heating? I just want to make sure it is not related to the spoiler control.

Thanks again for your help so far. I will post pictures and information about he car as soon as I get a chance.

elbeee964

Keith-

Here's a view (4th picture on down this page) of what was under my LHD C2's passenger seat as I swapped out seats. The silver box (sitting at an angle) I'm told is the tail control. (the middle one's a factory radio amp, the top one is the stock alarm.) I think you can make out a second screw helping to hold down that tail control unit, not just one.

I also understand that the car's wiring loom was all-options-capable, meaning some plugs may be there that your option list wouldn't/didn't use.

-Lonnie