davidwilson11

I had a look last night but saw so many posts I got lost a bit. I'm going to be removing the heater kit in the engine bay and would like to keep some sort of heat. I saw in one post how to fool the relay but it was a 993. Is this okay to follow on 1990 c4. Any help appreciated.

David

freedman

https://rennlist.com/forums/964-foru...-solution.html

FOS373

This ^^^^.

Super easy. CCU worked fine afterwards.

When installing the fab speed bypass, I removed the rubber boot, used some soapy water and it slid in fine.

davidwilson11

Superb mate. That's what I shall do. Thanks for the help muchio gracias

davidwilson11

So I put the new pipe in but haven't done the wiring. I'm assuming without doing the wiring then the problem is only cold air and no hot? It blows full on cold but as soon as I try and add in and heat it cuts the power to the heaters.

Keen to hear back before I mess with the electrics.

Vegas993

If you don't do the jumper, your fan speeds won't work properly.

alexjc4

Yup that is exactly what you get if you jist remove the motor and don't make any wiring mods. I used a single wire across the removed rear blower relay - works fine for me but different model years need different attention i think..

anto1150

That could cause battery drain

alexjc4

Not on my car (early 89) - according to my multimeter at least, but yes on some it could, even then I understand there's only scope for a very small drain similar to the alarm but that's why I said different cars need different attention.

xcoldricex

does the blower motor just affect the speed of airflow for the heat? is there a significant change in the heating capabilities without it?

Vegas993

There is also a blower motor in the dash, doing the relay jumper to the coil shown in the link above allows you to control the fan speed of that motor.

LPMM

Instead of the jumper method, any reason (perhaps besides cost) why the dummy relay method wouldn't work in the 964?

davidwilson11

LPMM that's where I started getting myself lost, there were a few posts and nothing that I could really pin down to a working solution?

alexjc4

The dummy relay would have exactly the same effect, just looks more factory

Vegas993

Once again, on later cars, your fan speeds won't work correctly and you may have a battery drain. When the cover is on the fusebox, they all look factory, lol.