Focus heater woes

[Bren]

I replaced the heater resistor in my sister's 03 focus as it only worked on one setting.

 

Now, a few weeks later, there is a burning smell and the heater again only works on one setting.

 

Is the cheapo ebay resistor at fault or is the motor on it's last legs?

[sierraman]

Shit cheap resistor, get one from breakers. You'll see where it's burnt out on the plastic.

[overrun]

Motor is fine, as it still grafts,

Your shitey resistor has shit itself, Cos it's shite.

[Sealtainn]

Cheap eBay parts strike again unfortunately

[mat_the_cat]

Isn't it the thermal fuse you're replacing, not the resistor? Or do you mean the whole resistor pack?

 

I've done a few now, all by word of mouth after the local garage was charging £300 for a dash out job!!! The fault on all of them was the thermal fuse failing, most of the time due to a sticky or in one case seized fan. So I just bought a pack from RS, pence each.

[sierraman]

No it's a variable resistor that's set on to a plastic mount, works the speeds.

[mat_the_cat]

...which is actually several fixed resistors (if you take it apart), with a thermal fuse. That's the part out on its own, at the opposite end to the screw hole on the plastic casing. I was just wondering whether 'resistor' in the OP was referring to the whole resistor module, or an individual resistor that had failed - which I hadn't come across before.

[Stanky]

If its anything like the Nissan Almera or my neighbour's son's Corsa D, the speeds are controlled by a variable resistor pack which relies on airflow for cooling. After a while the heat generated by the resistance - the intermediate settings between 'off' and 'Abigail' (topical, natch) - burn the circuit out and then it only works on full whack, which is basically the open circuit without resistance.

 

The pack sits in the air duct inside the car, after the pollen filter, but before the air gets directed to the screen/face/foot vents. My simpleton logic suggests that the problem is worse the lower the fan speed setting as the resistance is higher with lower airflow.

 

Anyway, mine took 17 years to expire then 20 minutes to fix. Next door's took 6 years to expire and about an hour to fix. 

 

get a genuine one from a breaker, or look on ebay for recon ones - I had to shell out £15 after haggling for mine, but its a massive chore having settings of 'off'or 'hurricane' to choose from. 

 

If its melting its because its not getting enough airflow - check that the air duct isn't blocked and/or the pollen filters clogged impeding airflow. If the airflow in the duct is crap you'll just keep blowing them. Its a shit design, but probably very cheap.

[srad34]

Genuine ford ones are not that expensive iirc.....worth checking

[sierraman]

It's literally a 30 sec job swapping these, I'd get a handful from the breakers for a tenner or so. I really wouldn't fuck around getting the soldering iron out.

[twosmoke300]

Smiley transits used to have them under the headlight behind the grille so they used to rust out instead . True story 😄