Heater Fan switch not working.

[DuncanM]

Hi Guys,

Just noticed today that my heater fans isn't working.

Any ideas where to look as first port of call?

Duncan

[morebeanz]

Given my recent faux pas with the starter motor, I'd start with...


...the fuses!

[350matt]

Check the control box hasn't had its ribbon pulled out ( its in the passenger footwell behind the carpet and check the ribbon at the switch end as well

Matt

[jesfirth]

mine failed recently and it was a taosted connection on the heater module box metnioned previously. if you open the box you can check all the connections.

[DuncanM]

Thanks guys, I'll take a look .

Duncan

[betty_swallocks]

what do you want the heater on for

[DuncanM]

It amused me somewhat when I googled the issue, and this came up

Issue 1 - Heater fan not working

I did the usual reset the ecu (plug in/out) and ended up with working cold fan/rear demist/air con, but no hot fan.

I removed the ecu and found the BUZ11 transistor for hot fan, and noted that the legs weren't even attached, and brown marks on the board around the connections.

I ordered, and subsequently replaced the transistor, and now have a working hot fan, along with the other controls. However, issue 2, which I now realise was there previously, but mistook for weird behaviour whilst doing the plugging/unplugging of the ecu.

Issue 2 - heatsink on heater ecu touches MBE case, and all heater controls go on (grounding the ECU?).

I believe this issue already existed as it was doing strange things when moving it about, and the heater fan transistor legs weren't connected to the board?

Any help from you clever people would be much appreciated