Heater fan gone - should I replace resistor pack with Jeep spec or PWM controller?

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ManicGTI
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Heater fan gone - should I replace resistor pack with Jeep spec or PWM controller?

Post by ManicGTI »

Hi all, my heater fan is seized solid and pops fuse on 2+ speeds, so have new motor and seal/foam pack from BW ready to 'pop in'.

While i'm there is there anything else I should be replacing or checking on the heater box while i'm in there?

In my travels across the interwebs it looks like over in the US it's a reasonably commonly recommended mod to bin the VW resistor pack inside the heater box and fit a Jeep spec resistor pack.  They're much cheaper than the VW parts and can be located in a way they can be  replaced without dash removal in the future.

There's a number of designs, but here's an example, they're 4 speed, easy wiring and fit to the air box easily according to the samba threads: https://www.ebay.co.uk/itm/167593390554

The other obvious option is PMV conversion for fan speed.

I don't 'need' either other above, I just want the heater working again really, but wondering if it's worth tweaking while i'm in there...
1990 - EJ251 - 5sp AAP - 'Weekender'

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Rik
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Re: Heater fan gone - should I replace resistor pack with Jeep spec or PWM controller?

Post by Rik »

I didn't change the resistor when I did my blower recently. And it is working fine now. But it might be easy insurance to do it when you're there anyway. Personal choice I guess.

Check the coolant hoses up there is my advise. Would be annoying if those were to start leaking while underway.
1986 tintop called Rutger. 1.6d (CS), 4 spd (ABF). Self-converted to camper in the Netherlands.

ManicGTI
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Re: Heater fan gone - should I replace resistor pack with Jeep spec or PWM controller?

Post by ManicGTI »

I guessed from the lack of response that it'l likely be fine to keep the OEM resistor pack.

Good point on the heater hoses, will take a look at them once dash off.  They're probably the only original heater hoses left on the van tbh. I wasn just planning on giving the matrix a clean tbh.

Have the dash loose and ready to pop out at the weekend.  Hoping the box rebuild isn't too painful.
1990 - EJ251 - 5sp AAP - 'Weekender'

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Rik
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Re: Heater fan gone - should I replace resistor pack with Jeep spec or PWM controller?

Post by Rik »

Splitting the box can be quite annoying if it hasn't been done before. The rest is very straightforward. I needed to change some of the foam as the old stuff had gone to dust. Good luck 👍
1986 tintop called Rutger. 1.6d (CS), 4 spd (ABF). Self-converted to camper in the Netherlands.

ManicGTI
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Re: Heater fan gone - should I replace resistor pack with Jeep spec or PWM controller?

Post by ManicGTI »

Removed and box split, fan was seized and resistor cracked in several pieces (air box showing signs of heat damage).

Planning on fitting an alternative resistor pack, currently liking the look of the MGF one, nice rectangular one with mounting holes.
1990 - EJ251 - 5sp AAP - 'Weekender'

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Jim San
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Re: Heater fan gone - should I replace resistor pack with Jeep spec or PWM controller?

Post by Jim San »

I did away with resistor pack, very happy with the variable controller, the first one failed after aBout a year and it was such an easy job to fix as I'd located it by the Ash that hole.
Worth the extra effort
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ManicGTI
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Re: Heater fan gone - should I replace resistor pack with Jeep spec or PWM controller?

Post by ManicGTI »

Jim San wrote: 29 Jan 2026, 14:14 I did away with resistor pack, very happy with the variable controller, the first one failed after aBout a year and it was such an easy job to fix as I'd located it by the Ash that hole.
Worth the extra effort
I've now ordered a controller, as well as a few typres of resistor pack to decide once they arrive.  I like the idea of a more easily replaceable resistor screwed in from outside of airbox.  MGF one has arrived and looked perfect, but i'd prefer one from a more common car (ie. not the jeep one the americans are using).  Nissan Juke one loooks promising.

On your PWM controller does it fully zero, or it sensible to add a on/off switch in series?
 
1990 - EJ251 - 5sp AAP - 'Weekender'

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