'87 944 AC issues - possible "amplifier"? Component location help please.

[Hoegenauer]

Hello to all the 944 Guru's -

My son bought his first P-car - an '87 944 - runs great but AC issues - it is a 134a converted unit by PO.

AC worked great about a half hour and then quit. We put 12V to the clutch and it engages. We jumped the relay at 30/87a and nothing. We jumped the pressure switch on the dryer and nothing. Fuse 29 is good. Relay was replaced for the fun of it. Light on panel illuminates when AC is turned on.



From the wiring diagram above - the points of interest are Connectors T63 and T31 in line from "Amplifier" to the low pressure switch, the amplifier and the "Additional Fuse Board" (fuse 3 and fuse 6). Where are these components? I really dont want to defile the wiring harness to chase wires if I dont have to. I read that the amplifier might be in the passengers floor next to door - we removed the glovebox and it is not there (only the radio amplifier)

Any help is appreciated!

Trey

[originalowner]

That is not the schematic for your year of car. Download the factory workshop manual and look over the correct schematic.

https://www.uriarte.dk/porsche944/garage/workshop.html
944 Workshop Manuals

[Jfrahm]

I think I read recently that someone got a bad new AC relay, designed wrong or built wrong. Bad in the box new. The dash switches also go bad.

The wiring diagram I glanced at (way different than pictured above) seems to show a High/Low pressure switch and a high pressure switch.

I would track back from the clutch with a power probe.

[Hoegenauer]

Originally Posted by originalowner

That is not the schematic for your year of car. Download the factory workshop manual and look over the correct schematic.

https://www.uriarte.dk/porsche944/garage/workshop.html
944 Workshop Manuals

Thanks for the reply - A little more help please - Your second link is exactly where I got the electrical schematic on the image (page 63 I think) for the one labeled Volume 4. Electrical. 90 MB, PDF. Electrical 82-87. Where is the correct schematic if this one is incorrect?

Thanks!

[originalowner]

Further down. Model year 87 starts on page 191. HVAC is on sheet 5, starting on page 207.

[Hoegenauer]

Originally Posted by Jfrahm

I think I read recently that someone got a bad new AC relay, designed wrong or built wrong. Bad in the box new. The dash switches also go bad.

The wiring diagram I glanced at (way different than pictured above) seems to show a High/Low pressure switch and a high pressure switch.

I would track back from the clutch with a power probe.

I only see two switches side by side on the drier - I dont find any other switches on the lines. But I agree - I would like to test but not destroy his nice harness

[Hoegenauer]

Originally Posted by originalowner

Further down. Model year 87 starts on page 191. HVAC is on sheet 5, starting on page 207.

Thanks! I knew I was deaf but I guess I am blind also - Sorry! That was stupid of me.