Thread: Cannot find the circuit??

That sounds like a bad earth to the becm.

There is a solid earth below the drivers seat, double check that it's tight and take it from there!

Hope it helps mate!

Blowers are on a separate relay in the fuse box under the bonnet.
Most of the other stuff is under the drivers seat fuse box, as Keithy says check the earths.
I would be taking a look at the under bonnet relays they have Id`s as per the underside of the lid.
Check the blower relays, the connectors in the fuse box may have de soldered from the board due to heat and age (quiet common) look for burning or melting under the relays.
If this is the problem you can solder the female spade connectors into the board again and use epoxy or buy a new fuse box, I did the former on mine years ago.

Thanks Keithy,

I checked the plugs in the front of the BECM but none actually had any relationship to that circuit but never say a system earth that time.
Will check it out more thoroughly in the morning.
Many thanks,
Shirley.

It's more to do with the blower speed controls which go haywire when the problem occurs. The blowers stay on but there is no ability to change the speed or regulate the climate control at all. The screen goes blank.
I removed all of the relays from the tray one by one just to see if any of them took the screen of the Climate control out but there was no response to that either so I would have to believe that Keithy is on the right track with the BECM earth of another plug that I haven't tried.
Might need to take the seat out to check it properly.
Many thanks guys,
Will post back to the group when the fault is rectified as there has to be others experiencing the same headache..

Cheers,
Shirley...

Originally Posted by RR P38

Blowers are on a separate relay in the fuse box under the bonnet.
Most of the other stuff is under the drivers seat fuse box, as Keithy says check the earths.
I would be taking a look at the under bonnet relays they have Id`s as per the underside of the lid.
Check the blower relays, the connectors in the fuse box may have de soldered from the board due to heat and age (quiet common) look for burning or melting under the relays.
If this is the problem you can solder the female spade connectors into the board again and use epoxy or buy a new fuse box, I did the former on mine years ago.

Hi Guys,

The fuse box is NEW, just replaced along with several lazy relays.
Double earthing under bonnet and all back to the battery (new) as well as extra earthing on the engine block as well.
New Pos+ feed cables to the alternator as well which has remedied a previous volt drop in the system so now all is running at 13.9V spec DC, all circuits active.
About the only place I haven't been thorough is the nasty bits under the driver's seat.
Might take a lot of extra care under there, hey?

Cheers,
Shirley..

Hi Shirl

I am with Keith that it is most likely an earth problem given the number of things which are affected.

It sounds to me like it could be a bad earth in the under dash area, unfortunately I don't know where the earth point connection is for that area, but someone on here or rr.net will know for sure!

It certainly can't hurt to check the BECM connections either

Good luck,
Steve

Originally Posted by Keithy P38

That sounds like a bad earth to the becm.

There is a solid earth below the drivers seat, double check that it's tight and take it from there!

Hope it helps mate!

Hey Keithy,
What a fun job getting that seat out... Man it was heavy.
Found heaps of spare change, some pens, lolly wrappers and lots of dirt & dust but no evidence of any probs under the seat with the BECM earth or any of the connections.

Either there is another circuit earth under the dash or a hidden relay somewhere because the fault seems to only occur after the system has been active for about half an hour. The sort of thing that might be associated with a lazy or over cooked relay.

Fortunately everything went back without problem, all circuits are working fine, no errors and no smoke. Especially no smoke.

The search continues.... Had a feeling it wasn't going to be easy.

Best wishes,
Shirley.

Sorry it took so long to get to this thread.

Both blower motors are earthed through the same point. E256 which is behind the drivers side kick pannel on the side wall (bottom of the A pillar). If ever the heater core Orings have gone in the car this earthing point can take a hammering through corrosion. (Best to check with a multimeter)

There was a TSP about bad clamping pressure on the main spade terminal to the motors - I'll see if I can find it.