1998 V70 Ac problem

sisterocean · Post by **sisterocean** » 18 Aug 2014, 09:37

I had a new compressor, dryer the works installed. The mechanic can only get the ac to work by manually engaging the fuse. Anybody out there have any ideas what to do. Mechanic is very frustrated. Very experienced over 40 yrs. Please help Thanks

Post by **Ozark Lee** » 18 Aug 2014, 14:14

I can't really figure out what he means by "manually engaging the fuse". The climate unit fuse should be in place for the system to work at all. Low system pressure or a bad low pressure switch (rare), can cause the compressor not to engage.

If it would help him, the schematics can be downloaded from this link.

http://www.volvowiringdiagrams.com/

The pagination is a messed up due to the way most of the schematics were scanned but most of the information is there.

...Lee

Post by **precopster** » 18 Aug 2014, 15:37

I believe he means if the switch is operated with the fuse in place it fails to operate however when the fuse it hot-disconnected and reconnected while the AC switch is on it does.

He may just find it easier to short the wires leading to the switch then break the wire leading to the fuse and place the circuit in series with the switch, perhaps by using a relay as well.

This will sort it out. On older cars unless something is obviously fried like a relay or switch you just need to get creative

sisterocean · Post by **sisterocean** » 19 Aug 2014, 19:41

Thank you will pass it on to him!