Quick Heater Control Unit Question

[Bigadz]

I have my repaired Heater control unit. I didnt actually take it out, it was already out when I got the car. I am putting it back in tonight.

I know its located at the back of the passenger footwell, do I just peel back the carpet and the 2x17 way ribbon connectors are there for it to plug back in, or is there a further board to remove? I have some contact spray to replace the carpet after.

Just thought I would ask as it might otherwise take me ages doing something wrong, thanks. Adam

[andydw]

The carpet at the back of the footwell is fixed to a removable panel, just pull the panel forward and out to get at the control unit. There are a couple of other control boxes in there too so its a good idea to have some velcro to hand to stick them to the lining material against the bulkhead so that the panel goes back cleanly.

[Bigadz]

Spot on, thanks.

[Bigadz]

Hmmmm it seems like there is more to the problem than the heater control unit. The 17 way connector is badly burnt on one pin, which is the one for the hot fan. It actually looks as though this wire has actually been cut following the burn out, this is hanging loose which I guess was to avoid a short out or something? I apologise I am not very electrical!

Hopefully it just means a new 17 way connector and then re wiring in. Does anyone know the correct part for this?

I have a picture if this helps..

[Bigadz]

http://img33.imageshack.us/img33/4900/132639769763...

Here is a picture of the culprit

[SimonSparrow]

Hi,

I'm just in the process of repairing mine and have the same burnt out connectors (this also happens to the light control box in the boot). I've by passed the 17 way connector for the burnt out pins only, using two wires soldered to the circuit board. Basically I carefully removed the two pins from the 17 way connector on the board, using a soldering iron and needle nosed pliers. I then drilled the remaining holes slighlty larger to take 2.5mm wire, which I then soldered in place.

The two wires leading to the burnt out pins on the wiring harness side were then cut and the ends replaced with some spade connectors, to join up with the two wires from the circuit board.

The two 17 way connectors are used as normal, but the burnt out pins are bypassed using heavier wire.

Hope this helps and makes sense.

Simon

[Bigadz]

Thanks Simon, I think I know what you mean, with my limited electrical brain! I would be extremely grateful if you had any pics of your fix?
What made you choose this route over replacing the connector? Was it the thicker guage wire to prevent the same burn out happening again?

[SimonSparrow]

Bigadz said:

Thanks Simon, I think I know what you mean, with my limited electrical brain! I would be extremely grateful if you had any pics of your fix?
What made you choose this route over replacing the connector? Was it the thicker guage wire to prevent the same burn out happening again?

No pics I'm afraid. I used wires to bypass burnt out connections on the light control unit a few years ago. The reasons being, if the orginal connector had burnt out once, it will probably do it again, and also I could install the two bypass wires more easily than replacing the two 17 way connectors. The bypass wires have a break made with spade or bullet conenctors, so the box can still be removed from the car.

[Bigadz]

Thanks again Simon, I will give it a shot and hook up the bypass using a heavier wire. So your bypass came directly out of case from the board?

[SimonSparrow]

Bigadz said:

Thanks again Simon, I will give it a shot and hook up the bypass using a heavier wire. So your bypass came directly out of case from the board?

Yes, where the 17 way connector fits into the board, there are 17 pins bent at right angles and soldered in. I removed the two that corresponed to the burnt out ones buy unsoldering them. It was into the two holes left that I put the the two wires to bypass the connector for those pins.

I need to replace the transistor on mine as the hot fan now runs all the time, but I won;t be able to do this for a couple of weeks, so no chance for pics for a while.

Just saw, this picture shows the same thing but for the light control box

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

Edited by SimonSparrow on Friday 13th January 08:33

[Bigadz]

Nice Simon, thanks. I brought 3 transistors so I have a spare one. If you need I can send you one for free, just message me your address.

Adam

[FarmyardPants]

After a few years of working intermittently, my hot blower now refuses to work at all. I've taken out the heater control unit and it looks brand new inside, no burnt out pins or any other sign of damage. The cold fan works. Any ideas on what to look at next. Do I need a new transistor