Right then, here are the results!!!!
The lower control board in the heavy has developed "the" problem.
I've connected the older spare hevac and it all works. So I'll connect
my working face panel to the older lower driver/controller?? Panel and see how this is going to go.
πŸ€”
 
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So....i can set the left hand blend motor to 20Β° using the old control panel and then plug my original panel in and regain the aircon. Which I think is more needed.
Very slowly starting to lose interest in this thing....πŸ˜”
 
Later vehicles have a relay for the compressor. Early & late HEVAC have different output circuits Early HEVAC expects the full compressor clutch current, so don't work properly in later cars. There's a TSB somewhere about this somewhere. will look for it.

What year is the car, and what HEVAC part numbers do you have ?
 
Later vehicles have a relay for the compressor. Early & late HEVAC have different output circuits Early HEVAC expects the full compressor clutch current, so don't work properly in later cars. There's a TSB somewhere about this somewhere. will look for it.

What year is the car, and what HEVAC part numbers do you have ?
It's an october 99 plate with later hevac and external relay in the fuse box πŸ‘
 
RAVE TSB section does not allow me to "print to PDF", so & printed it on paper & scanned it for you !!
Thank you very much for that.
It's because the early hevac I've got is faulty towards the current draw..
I'm putting it back together with the temp set at 20...
I've got Too much to do today and tomorrow to be aggravated with a minor issue like this...

It's been tough the last two years dealing with my own mental issues, two teens and an adult son who can't leave due to financial reasons with his own crap, trying to be mum and dad along with to trying to run a business. This I don't need right now .....
I'm sorry to let that out into the air upon you kind people...
πŸ₯Ί
That was tough πŸ˜”
 
We all have little rants don’t worry.
Strangers can help easier sometimes than people face to face, once you come out the other side of the wringer it will all work out.
I went through 2 of the dam things, I am quite slim now :p .

J
 
You could bypass the relay so the HEVAC thinks it's the early car !!

If you don't have the extra relay, it could also be the AC compressor clutch needs re-shimming ? If the gap gets too big with wear, the clutch doesn't engage reliably.

1708182818631.png
 
Later vehicles have a relay for the compressor. Early & late HEVAC have different output circuits Early HEVAC expects the full compressor clutch current, so don't work properly in later cars. There's a TSB somewhere about this somewhere. will look for it.

What year is the car, and what HEVAC part numbers do you have ?
Early cars drive the AC clutch direct, later cars drive is via a relay. The relay does not draw enough current for the early HEVAC so it throws a fault. There are 3 possible mods, one is to add a resistor across the relay, two is to remove the relay and fit a jumper wire across the contacts, the third is to change the output drive MOSFET in the early HEVAC to the later device.
 
Thank you very much for that.
It's because the early hevac I've got is faulty towards the current draw..
I'm putting it back together with the temp set at 20...
I've got Too much to do today and tomorrow to be aggravated with a minor issue like this...

It's been tough the last two years dealing with my own mental issues, two teens and an adult son who can't leave due to financial reasons with his own crap, trying to be mum and dad along with to trying to run a business. This I don't need right now .....
I'm sorry to let that out into the air upon you kind people...
πŸ₯Ί
That was tough πŸ˜”
It can only get better.
 
You could bypass the relay so the HEVAC thinks it's the early car !!

If you don't have the extra relay, it could also be the AC compressor clutch needs re-shimming ? If the gap gets too big with wear, the clutch doesn't engage reliably.

View attachment 310619
I tried that and no joy, I've no doubts of the aircon clutch tbh. It's been working fine and works with original control panel when it's plugged in Mr @pwood999 🀷
 

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