Speedometer sensor location
 

I have a 79 930, it does have an 87 motor but I would not think that would effect this.
Speedo works intermittent.
I under stand that the sensor connection is under the tunnel plate in the car,mis that correct?
Where is the sensor located on the car, I have appartly misidentified it as the backup light switch,mwhere is it.
Also on the back of the speedo itself there should be a white/ red wire I do not have that can someone tell me what the wire is for/ from. I have hot and prong with 3 Browns and the one with one brown.
Any help would be appreciated.

Hi, I'm assuming that the 930's sensor is the same as a Carrera's

Its located on your rear left side. It's just beside the top of your inside axle. Taking the wheel off make's it much easier to change. You need an allan wrench to remove it

Normal Carreras have the speedo pickup on the right side.
Search and find numerous threads on testing the pickup before you start replacing it. In my experience, speedos go intermittent a lot more often than pickups
When the speedo stops, does the the odometer still work? If so, the problem is not the pickup...it's the speedo.

Thanks for the correction. My mistake as it is on the right side.