P38A Hvac motor query.

Flossie · Nov 2, 2023

A friends 38 only blows cold on the drivers side, passenger side works as it should. Its been like this since he's had it 18 months ago..
The pic is of mine showing the duct repair from yesterday, now...is that motor the one at fault? Looks replaceable without removing the whole dash? Or...just to get him through winter until he can do the job properly, can it be manually set to hot and locked in the hot position?

Flossie · Nov 2, 2023

Oops, forgot the pic.

kermit_rr · Nov 2, 2023

It's the bottom one as you look at it from the driver's footwell. The first one to get to.
Easy to remove on mine, while i fixed it i hooked a bit of wire to the manual flap adjuster

kermit_rr · Nov 2, 2023

i think i've got some spare pots if you want to have a go at a fix. i've got a couple of motors too.
it might be worth resetting to the mid point and seeing if it starts working again

Rubberknees · Nov 2, 2023

Flossie said:
Oops, forgot the pic.View attachment 301612

In the past to get me through a winter and to get the motor to the hot position I cut the cable and using crocodile clips and a piece of wire I used a 9v battery to move the motor to the hot position. Look in rave at wiring diagram for motor wires as I've forgotten colours. By alternating + and - you get the motor to move either direction.

Flossie · Nov 2, 2023

kermit_rr said:
It's the bottom one as you look at it from the driver's footwell. The first one to get to.
Easy to remove on mine, while i fixed it i hooked a bit of wire to the manual flap adjuster

I've got rave in a hard copy but it doesn't do the last 38s with egr and maf which we both have. Dunno if the hvac dash motors are the same regardless but the pic in RAVE shows a motor on the passenger side blower, near the A post, and one either side of the heater box, I thought (dunno why) that all 3 were on the heater box. The pic above is the motor looking down through the speedo cluster and although I wasn't looking, that's the only motor I noticed on that side, that's the rhs of the heater box. Can't have another look as I've buttoned it all back up now.
Just wondering for a quick bodge if it's possible to remove that motor and turn the workings left behind to give him some heat until he has time and weather to fix it proper?

kermit_rr · Nov 2, 2023

The motor is reachable from underneath though i think there's a plastic tube in the way. If you take the motor off then you just have the flap arm where a cable would have attached. Don't move to fully hot or you'll soon cook.
It's the one with the blue band

kermit_rr · Nov 2, 2023

Flossie said:
all 3 were on the heater box. The pic above is the motor looking down through the speedo cluster and although I wasn't looking, that's the only motor I noticed on that side, that's the rhs of the heater box.

the grey one is distribution, the blue one is temperature

Flossie · Nov 2, 2023

Rubberknees said:
In the past to get me through a winter and to get the motor to the hot position I cut the cable and using crocodile clips and a piece of wire I used a 9v battery to move the motor to the hot position. Look in rave at wiring diagram for motor wires as I've forgotten colours. By alternating + and - you get the motor to move either direction.

Have you seen the price of 9v batteries! Lol! Recently had to get a couple for my smoke alarms..£9 , nine bloody quid fer two!!.
His motor might be dead though?
Wonder if nanocom will work it or not IF the binnacle cluster is out? We did try with the nanocom last summer but it was inconclusive, can't remember why but I'm still learning how to use it plus mine doesn't seem to go wrong much to need the nanocom, goes wrong lots, just the nanocom isn't needed for leaky leak offs, leaky injector seal, matrix leaks, tyres going flat, oil leaks, pollen filter leaks, oh..I did need it to find an abs sensor fault but even then it diagnosed the wrong one! Rhr is lhf...phfff...

kermit_rr · Nov 2, 2023

my passenger side one didnt work.. i didnt know about using 9v batt, so flashed it with 12v from the ciggy lighter
it worked perfectly thereafter

Flossie · Nov 2, 2023

kermit_rr said:
The motor is reachable from underneath though i think there's a plastic tube in the way. If you take the motor off then you just have the flap arm where a cable would have attached. Don't move to fully hot or you'll soon cook.
It's the one with the blue band

Blue, the one in my pic then?
The plastic pipe in the way is probably that duct shown in my bike inner tube repair, that gets in the way of everything on that side.

Flossie · Nov 2, 2023

kermit_rr said:
my passenger side one didnt work.. i didnt know about using 9v batt, so flashed it with 12v from the ciggy lighter
it worked perfectly thereafter

They don't like it up 'em! :vb-lol:

Flossie · Nov 2, 2023

kermit_rr said:
the grey one is distribution, the blue one is temperature

His distribution works fine. The grey one is on the opposite side of the heater box to the blue one or on the left hand side blower motor?

kermit_rr · Nov 2, 2023

Flossie said:
His distribution works fine. The grey one is on the opposite side of the heater box to the blue one or on the left hand side blower motor?

I'm lost now!
the pic is drivers side, with 2 motors, one grey (screen/vent/feet distribution), one blue (temp distribution)
the passenger side just has one for the passenger side temp

is that what you;re asking?

Flossie · Nov 2, 2023

kermit_rr said:
I'm lost now!
the pic is drivers side, with 2 motors, one grey (screen/vent/feet distribution), one blue (temp distribution)
the passenger side just has one for the passenger side temp

is that what you;re asking?

Sorry my fault :vb-weyes:

. Just had a look at rave and my pic again and I've realised there are two motors there and I thought it was one big one doing one job not two motors doing two jobs, and now your previous posts make sense.

Pic from rave After thumbing through further pages, so blue is the bottom one and grey is the one above.

Flossie · Nov 2, 2023

this is what confused me, 8 in rave is "servo motor , fresh air and recirculate air vent flap'

Rubberknees · Nov 2, 2023

Flossie said:
Have you seen the price of 9v batteries! Lol! Recently had to get a couple for my smoke alarms..£9 , nine bloody quid fer two!!.
His motor might be dead though?
Wonder if nanocom will work it or not IF the binnacle cluster is out? We did try with the nanocom last summer but it was inconclusive, can't remember why but I'm still learning how to use it plus mine doesn't seem to go wrong much to need the nanocom, goes wrong lots, just the nanocom isn't needed for leaky leak offs, leaky injector seal, matrix leaks, tyres going flat, oil leaks, pollen filter leaks, oh..I did need it to find an abs sensor fault but even then it diagnosed the wrong one! Rhr is lhf...phfff...

If the the potentiometer has failed nanocom wont move it. Well wouldn't on mine, just tries to move the other blend motor. Read somewhere it was a gremlin in the nanocom software.

Rubberknees · Nov 2, 2023

Flossie said:
Have you seen the price of 9v batteries! Lol! Recently had to get a couple for my smoke alarms..£9 , nine bloody quid fer two!!.
His motor might be dead though?
Wonder if nanocom will work it or not IF the binnacle cluster is out? We did try with the nanocom last summer but it was inconclusive, can't remember why but I'm still learning how to use it plus mine doesn't seem to go wrong much to need the nanocom, goes wrong lots, just the nanocom isn't needed for leaky leak offs, leaky injector seal, matrix leaks, tyres going flat, oil leaks, pollen filter leaks, oh..I did need it to find an abs sensor fault but even then it diagnosed the wrong one! Rhr is lhf...phfff...

Have you never been to Poundland

Datatek · Nov 2, 2023

Rubberknees said:
If the the potentiometer has failed nanocom wont move it. Well wouldn't on mine, just tries to move the other blend motor. Read somewhere it was a gremlin in the nanocom software.

That's the 4th blend motor and as it's rarely used it often doesn't work.

kermit_rr · Nov 2, 2023

Datatek said:
That's the 4th blend motor and as it's rarely used it often doesn't work.

Worked on mine

P38A Hvac motor query.

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