Heater / ventilation fan / blower question

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UPDATE

OK...I took the truck to the dealer and was advised that the issue is NOT the AC Amp, but instead the "Center ECU for AC Control" has a short in it and is only pushing 9v (instead of 12v).

My dealer has a policy of not giving out P/N (I understand) but I cannot for the life of me identify the P/N. Can anyone help? I believe this part is located behind the center facia (AC Controls - Radio) and somehow (I believe integrated into the AC Amp.

Many thanks!
 
Blinking "RrDEF" (Rear window defogger switch indicator light) and blinking "RrACSW" (Rear A/C ON-OFF switch indicator light) together = Normal operation.

Just curious....are you pulling the codes from the manual? I havent been able to find what the different codes mean. Any help would be much appreciated. Thanks.

Or does anyone know where I can get a look at DI-620?
 
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Found it - Part on order ( 8279160030) - will now have a working blower.

Just installed - NOT the issue.

Really getting frustrated...if this truck weren't part of the family...

Could it now really be the amplifier?

Words cannot describe the frustration with the dealer that I paid to diagnose and tell me "yep, 100% certain it is the junction box".....
 
Not that most LC folks would care ;) - but always felt one should update any link they post on when new info is obtained.

Anyway, after many months of more parts (more returns) and much more frustration (including turning the truck over to the dealer 2x - the first being a fix that was "corrected" - but when I picked up the truck - while driving away noticed the blower didn't work.

FINAL SOLUTION (UZ100's w factory phone only) - the phone "mute" lead had shorted - net was fan speed was now stuck on low. Insulated lead - all works perfectly (and the tilt away wheel now works as well???)

Anyway, hope that helps someone.
 
Not that most LC folks would care ;) - but always felt one should update any link they post on when new info is obtained.

Anyway, after many months of more parts (more returns) and much more frustration (including turning the truck over to the dealer 2x - the first being a fix that was "corrected" - but when I picked up the truck - while driving away noticed the blower didn't work.

FINAL SOLUTION (UZ100's w factory phone only) - the phone "mute" lead had shorted - net was fan speed was now stuck on low. Insulated lead - all works perfectly (and the tilt away wheel now works as well???)

Anyway, hope that helps someone.

Interesting find. Thanks for posting. They must have been a bugger to discover and would require some intimate knowledge of the workings of the vehicle's electronics.
 
I know I've seen this problem on the board before but don't remember the resolution.

Have you done the climate control system self check ?

The A/C panel can do a self diagnosis. DI-620

1. Turn ignition switch to on while holding down the A/C and Recirc/Fresh switches.
2. All the indicators should flash on and off at 1 second intervals.
3. Any malfunction will be indicated by the trouble area's light blinking. A table to translate the lights to a trouble spot is on DI-624 or post it here and I'll look it up.​
main problem
FAN DOES NOT SHUT OFF
self check errors:
flashing lights on
rear window
rear defroster
front defroster
fan speed #2
Have already tried swapping out danso control blower module
same results




I know I've seen this problem on the board before but don't remember the resolution.

Have you done the climate control system self check ?

The A/C panel can do a self diagnosis. DI-620

1. Turn ignition switch to on while holding down the A/C and Recirc/Fresh switches.
2. All the indicators should flash on and off at 1 second intervals.
3. Any malfunction will be indicated by the trouble area's light blinking. A table to translate the lights to a trouble spot is on DI-624 or post it here and I'll look it up.​
 
I know I've seen this problem on the board before but don't remember the resolution.

Have you done the climate control system self check ?

The A/C panel can do a self diagnosis. DI-620

1. Turn ignition switch to on while holding down the A/C and Recirc/Fresh switches.
2. All the indicators should flash on and off at 1 second intervals.
3. Any malfunction will be indicated by the trouble area's light blinking. A table to translate the lights to a trouble spot is on DI-624 or post it here and I'll look it up.​
main problem
FAN DOES NOT SHUT OFF
self check errors:
flashing lights on
rear window
rear defroster
front defroster
fan speed #2
Have already tried swapping out danso control blower module
same results
 
Waking up this valuable thread.
My blower motor wont run anymore, LC 100 year 2000, manual climate controls.

This is my current status after troubleshooting:
* Have taken out the motor, and its spins when I connect it directly to a 12V battery.
* Measured the voltage on the two-lead blower motor connector (not on the controller harness), and its reads approx:
- Fan speed OFF: V
- Fan speed LO: 10,2 V
- Fan speed M1: 10,4 V
- Fan speed M2: 10,43V
- Fan speed HI: 11.7 V

Questions
1. If the connector above can deliver 11.7V on HI, shouldn't it be able to turn the motor (as it can be turned by a 12V battery) ?
2. May it be the case that there (due to some unknown cause) is voltage drop when there is a load/resistance presence?
3. I assume a healthy motor would turn on stable lower voltages also, as that is he means of controlling its speed?
3. I have not yet been able to remove the controller unit, as it seem to be a nightmare to remove as it's placed so have not been able to measure according to the instruction, but do my measures voltages above on connector make sense or are they really off?

Greatful for any input given
 
What do you mean "Manual Climate Controls"? Afaik, there is no such thing in an EU/US 100-series. The model with 3 rotary switches is still an automatically controlled AC/heater, in that you set the temperature, not the heating or cooling power. The manual version was available as an option in OZ and GCC, according to TMC.

Anyhow, presuming you have the standard controls, the blower motor is controlled by a relay on the positive lead, and a speed controller on the negative side. These 2 circuits have separate fuses as well.
If you measure the voltage directly on the fan motor, and get anything over 3-4 volts, the fan should run. That is if you have both test leads directly to the motor terminals.
You can test the relay on the plus side by connecting the voltmeter between the blue/red cable and chassis. The reading should be equal to battery voltage.
The voltage regulator can be checked with the meter between blue and battery plus, but it probably needs a suitable load to work.

The motor draws about 12 Amps at full speed, i.e. about 144 watts (Spec=140W). That means the motor resistance is around 1 ohm.

Btw, is there a Webasto or similar installed?

Edited the cable colours.
 
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OK great that you sorted out that with auto/manual climate control.
Will do a new voltage measurement on motor terminals with the load present.

Good you pointed it out, in fact I have a Webasto heater installed, that may explain why the cables to the fan seem tampered with. Anything to watch out for here related to the Webasto?
 
Standard Webasto install includes 2 relays in a Webasto relay holder. Only one relay comes in the kit (which suits most cars), but the cruiser needs two, one for the positive side to circumvent the OE on-off relay, and one on the negative lead to circumvent the speed controller. In addition there is a resistor of 1-3 ohms to bring the fan speed down to a reasonable speed and power consumption.
In my car, the relays are spliced in next to the blower motor, with the relay block hidden behind the glove box.
Some cars have the relays controlled by the Aux signal of the Webasto remote control, so that you can choose only engine, or engine and room heating.
The cloth wrapped cables in this pic are the Webasto loom. (Fuses in this location are on 2003- models)
P9150696-s.jpg
 
Thanks for input.
Wonder if the Bosch Relay pictured here is part of the Webasto installation? If I remove it there is zero voltage to the blower, so it plays some role. The brown leads connects with the motor connection leads (apparently smaller area cables than the OEM ones...).
Can this relay be failing in some way, causing voltage drop on load or similar?

Haven't followed the other lead to see if there is a second one, but there is a quite large ring-formed ceramic piece below this relay, think it might be the resistor (not pictured).

Could the Webasto parts be failing me?
I never use the Webasto anyway since the Minicall pager is failing to engage 50% of the times, so I would sacrifice it if I could gain a worikng fan.

IMG_7076.jpg
IMG_7077.jpg

IMG_7080.jpg
 
I think you are onto something. That's the kind of relay used for the Webasto, and the circular ceramic is a 0.9 ohm resistor (gives 1 O together with the cable loss). The blower motor would be connected to the 30-terminal, and the 87a (NC) to the original loom/supply, and the 87 (NO) to the chassis through the resistor, if this relay is on the negative side. Those relays can fail, so an easy test is to try another one. Just don't use a Biltema brand, as those have a different pin config. (Seeing you are in the nordics)
Not the neatest install, but can still be functional and safe.

Edit: There might be another relay somewhere, on the main Webasto control control board. Depends on which version you have. Follow the brown cables?
 
Update

Replaced the Webasto relay. No luck.
Measured the voltage over the connector terminals with motor attached (and fan speed HI), zero volts.
Without motor attached it reads 11.6 V. Can this be some modulated speed control reading only measurable without load?
This is beyond my very basic electrical skills, can't understand why voltage drops to zero under load.

I can conclude my controller unit is different from the one the TS posted. Suppose it is the difference between his manual and my automatic control. Sad part is that my controller sits on the plastic vent chassis (see the heatsink through the plastic) on the far end side back to back with then engine room wall. See pic with the mirror. Expect it to be a nightmare to get get that screw out, approx 4 cm headroom for a screwdriver.

Must also be very tiny electronics into this controller board, as one can see from the mirror-image the casing is just some 5-7 mm tall. Nothing like the TS posted images. Also I have four leads into the controller, while TS has five and the trouble shooting manual mentions five. Someone sitting on an similar troubleshooting for Automatic Climate control, or know the partno for my kind of controller?

Haven't identified the second Webasto relay yet, but could that really stop power to the fan? Thinking it might just stop the Webasto override of shot-off fan...


Thin controller in a bad location
IMG_7101.jpg




Four leads to controller, not five
IMG_7103.jpg
 
ISTR that a lot of these problems were caused by the connectors on the back D pillar, drivers side? The cabin vents leak water down onto the harness connectors back there, and cause resistance and ground probs..
 
What is the month of production, and is it a LHD European version (First sold thru Swedish dealer maybe?)
Attached pdf is for up to 2000.9 production. Something doesn't match re 4-pin / 5-pin plug...
 

Attachments

Yes, LHD European version. No import.
Variant UZJ100(N)
Version UZJ100L-GNPEKW(
Manufactured Year-Month 2000-02

Below is a picture of the markings on the controllers connector slot. I rotated it 180 degrees for your reading convenience.
Only four markings: VM, +B, SI, GND.

So, has M+ and M- been combined into one VM ?
Strange.

Thanks a bunch for putting time and effort into this, appreciated. Great with the troubleshooting guide, a great asset.

IMG_7102.jpg
 

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