Mk4 Fiesta heater controller

I'd find out what the component was and just change that. 30 seconds with a soldering iron would see it swapped out.

I agree with Conor, problem is working out the part number. Could you take a peek at another PCB and note the IC's type number, it will be standard one and that would be easy to swap out?

Looking at the photo - it looks as if that IC feeds straight out to a pin on the connector, at the bottom of the frame. The large pin on the right side of the IC is intended for heat dissipation, which suggests it is intended for controlling some current. It might be worth following the track from the pin on the top left - that looks like the input and where ever it comes from might also show signs of damage.

FWIW it looks like a transistor, it may be worth trying to get some kind of generic one that will switch 12V, but as you can't see the part number your a bit stuck.

As all manufacturers will try an make everything a common as possible, i'd say your in with a good chance that the PCB is the same.

Steven

I put the part number into google and it came back with the a breaker selling the whole heater control panel on a mk4 Fiesta.

My instant thought seeing the picture of the pcb was that scorched component was a power transistor, but after a few seconds wondered if it would be more likely to be a thyristor as the board is controlling a fairly high current (high relative to most electronics) to the fan. Not sure if they make thyristors that work at low voltages, but sensible to control the fan with mark/space waveforms than DC resistance to save on heat dissipation if they can be used. Having said all this, I am now back more in favour of it being a power transistor. Even so, the fact its scorched, does not mean its faulty or that a replacement would not do the same, but its a good bet replacing it would cure the fault.

NOW totally Off Topic: This damn military helicopter (HH-60) that has been flying over my roof in circles for the past 4 hours is just about sending me insane. Had F-15's flying low all day today and now they have stopped there is this damn chopper going round and round in circles. I'm moving to Vermont!

Mark

Oddly, my heater failed in the same way last year and I replaced the PCB with a replacement from ebay only to discover it was the control valve that was broken.

I still have the original (presumed working) PCB which I could send you if you want it...

However, mine has the part number XS6H19A522BA on the cover, which suggests it is slightly different, if just a new revision of the chip or something. (Mine is a '00 fiesta)

The PCB itself has this printed on it in the corner:

(PWB7123) XS6F-14A608-BA

Yes I'd found that but daughter's facia is different as it has a cigarette lighter socket included and the right button is clearly marked "A/C" (it has aircon). On the Bradgate picture there's no socket and the button is not labelled and may be a blank. I don't know if the PCB is the same on A/C and non-A/C models, hence my original question. It then occured to me that the printed part number I quoted could be that of the cover, not the board itself and that would be the same for all variants.

I'd happily replace the blown component if I knew what it was. It's not just scorched - the surface is blistered and bulging.

It's the DC that gets you, not the voltage, you PWM with transistors.

This PCB just controls the heater control valve with a PWM output based on the position of the rotary temperature selector (variable restistor), and holds two bulbs for panel lighting.

I think on higher spec Fiestas it also deals with the A/C and recirc buttons, but not on mine...

On Mon, 29 Dec 2008 19:00:59 -0000, I waved a wand and this message magically appears in front of Mark:

Could I interest you in this SAM missile?

could you read the number for the burnt component mentioned by the OP, i am curious now, the lettering starts PH 52 till the burnt out part.thx

Appears to say:

PH02

52 - 10A

Which doesn't bring up anything relevant on Google.

Thanks - that's worth a try. I'll email you ...

-- Reentrant

replying to Reentrant, Valerio wrote: I'm Valerio and I'm italian. I've a fiesta and I am searching a New component PH98 52 - 10 A or its data sheet. Please help me! Tnks

The part name is IRFL4105, check if it matches your control board: