alan914

I recently installed a radio in my 968 and the Large green ignition switch power wire has gone dead.

When I follow this wire in the wiring diagram it connects to a rectangular "connector box" labeled "P50". I don't find another "P50" anywhere, nor do I know where I should be looking for a matching "P50".

Anyone know how to follow the many connection boxes on the wiring diagrams? Or where the other end of the green ignition switch power is?

onspeed

check your fuse.

alan914

Fuses are good...I checked the radio fuse in the under hood fuse box, as well as the others...all good?

onspeed

You've confirmed the wire is dead with a voltmeter?

I don't have a 968, so I can't help with the connector box thing... although I'd imagine it being under the dash somewhere... I'd say driver side.

944Ross

On most 944's the radio power comes out of a Radio Relay. If you are familiar with GM cars, it's the same deal; after you turn off the car, the accessories are hot until you open a door or 10 minutes pass. Not sure if they still did that on 968's but I would assume so.

alan914

Thanks for your reply!!

I did test with a voltmeter. Also, when I jump to this terminal from a hot terminal the radio works, which validates that this is the problem. Possibly another fuse box somewhere?

944 and 968 wiring at least for the radio are very much the same as are the wiring diagrams. Symbols definitions should be the same.

In flow charting there are on-page and off-page connectors that you can follow process flow from page to page or section to section. I'm assuming wiring diagrams are similar.

944Ross

To be honest, the early 944 wiring diagrams don't make sense to me, late-model ones are a little less arcane.

87 944 C

post up or pm me the diagram

alan914

Thanks for the replies. I have uploaded a jpeg of the wiring diagram to this reply. The wire path I'm looking for is the top one to the left out of the radio marked Gn 2.5 which terminates to the P50 Rectangular connector.

I did find a blown fuse on Fuse 36 (15 amp). I gave up and just tested each one with a lighted electrical tester until I found the one. Visual inspection I just missed it. This did solve the problem; however, I am still interested if anyone knows how to read the "connectors" on the wiring diagram.

Thanks to all of you for your answers!!

jpk

Look at the edges of the diagram, and you'll see letters across the top and numbers down the side, kind of like a map.
The diagrams are broken down into 10 "sheets" + additional sheets for Cab and tiptronic. The sheets are made up of three pages, and each one goes from A - P across the top. The sheets are numbered down the sides as multiples from 1-10.
So P50 is referring to column P, row 50, which you'll find on the very right side of sheet 5, at the very bottom. When you look down into that corner, you see a box marked M82, which is where you are coming from in the diagram (i.e the location of the P50 box in the pic you posted is column M, row 82 on sheet 9)

alan914

thank you John!! You hit it on the head. M82 follows to fuse 36 which is the one that was blown.
especially thank you for explaining how these diagrams fit together, now I can trace all the leads.

Alan