heater blower

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hank123
Can find the S1 radio
Posts: 27
Joined: Tue Jun 16, 2015 2:18 pm

heater blower

Post by hank123 » Thu Jun 15, 2017 3:12 pm

Hi, can anyone help please. Where is the heater blower relay located? I certainly can't find it!!!!

xmexclusive
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Re: heater blower

Post by xmexclusive » Thu Jun 15, 2017 3:33 pm

It is an open frame relay soldered into the control module pcb inside the heater blower.

John

hank123
Can find the S1 radio
Posts: 27
Joined: Tue Jun 16, 2015 2:18 pm

Re: heater blower

Post by hank123 » Thu Jun 15, 2017 4:08 pm

Hi John, thanks for your reply. I have just replaced the hedghog?-Resister? screwed to the motor, is that what you are referring to? I'm going nuts trying to find out why the motor isn't working. It works when connected to a battery. My car has the electric controller fitted, so it's hard to know where the problem is. I have asked if anyone has a controller on this site, just in case it's that causing the problem. Had the car just a week, unable to ask last owner questions as he has passed away. Any further help would be most welcome. Gary.

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Re: heater blower

Post by xmexclusive » Thu Jun 15, 2017 4:58 pm

Yes.

When you say it works when connected to a battery need a bit more detail.
Is that running connecting directly to the motor and it runs at full speed.
Or is it running connected to a battery through the control module.
Worth indicating where you are located as it would be a pity to find out later someone who could help directly was close by.

The XM electronic control panel has leds and push bottons.
These are easy to swap and I could supply a known good one on loan to test out.

The are at least two versions of the simpler controller with knobs and sliders.
These seldom fail and are much more difficult to swap.
Testing by swapping these controllers is not the way to go.
Plug in a test circuit and prove the wiring and fan good before a controller change.

I am afraid there are a lot of cheap Chinese copy control module on ebay that fail to work in an XM.
If you have obtained one of those then the car may actually have no other problems.

Have you read the XM Heater Control post in the self help section?

John

hank123
Can find the S1 radio
Posts: 27
Joined: Tue Jun 16, 2015 2:18 pm

Re: heater blower

Post by hank123 » Thu Jun 15, 2017 5:08 pm

Yes connected directly, ran at full speed. I'm near Cambridge. My controller has 3 rotating knobs, and one slider which is for fresh air. I have no wish to replace the controller, just trying to find which part of the system is at fault.

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Re: heater blower

Post by xmexclusive » Thu Jun 15, 2017 5:18 pm

Hank

Ran at full speed with wires connected direct to fan.
Or ran at full speed with wires connected through the hedghog module on the fan.
All the dash controller is is a simple rheostat (variable resistance) with a knob to set it.
The hedgehog module sees the set resistance and alters the voltage to the fan to set its running speed.
No fan or full fan are common defective hedgehog module failures.
New Chinese modules can be a failure in an XM.
Might be worth identifying where you sourced yours.

John

hank123
Can find the S1 radio
Posts: 27
Joined: Tue Jun 16, 2015 2:18 pm

Re: heater blower

Post by hank123 » Thu Jun 15, 2017 9:37 pm

John

It was run strait from the battery via the 2 main wires that come from the motor, the ones that connect to the plug inside the car. The old hedgehog was in place when the test was carried out. The new hedgehog was fitted afterwards. The unit was then connected back inside the car. It still failed to work. Gary.

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Re: heater blower

Post by xmexclusive » Thu Jun 15, 2017 10:02 pm

Hi Gary

The most likely suspect is the new hedgehog for the reasons I have stated in the earlier answers.
The wires and plugs on the fan for the hedgehog are just long enough to plug into a replacement hedgehog outside the fan.
So you can test a new one this way before installing it.

John

hank123
Can find the S1 radio
Posts: 27
Joined: Tue Jun 16, 2015 2:18 pm

Re: heater blower

Post by hank123 » Thu Jun 15, 2017 10:21 pm

Hi John.

I hear what you are saying John, but the blower didn't work with the old hedgehog? Or am I missing something here. Oh dear, have I become one half of the thicky twins? Gary

xmexclusive
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Re: heater blower

Post by xmexclusive » Thu Jun 15, 2017 11:38 pm

Electrical equipment on XM's take quite a bit of our time on here.
Starting straight in without a bit of help is always difficult.

The motor is the simple electric bit and you have proved that it is not the motor brushes because the motor runs with a direct supply.
If you linked the that direct supply from the 4 pin brown plug red and black wires then you have proved car wiring and fuses.
You need the ignition switched on to do that checking.
If you linked direct battery to fan then you need to do the car wiring and fuse check listed above.

I will try to explain how the remaining items work.
The hedgehog has two output pins to go to the fan motor.
It has a chunk of electronics and relay to control fan speed by varying the output voltage to the fan.
The voltage it varies is the 12 volts from the car wiring, this will be found on the thick red and black wires of the 4 pin plug into the hedgehog.
The other two thin wires into that 4 pin plug come from a rotary variable resistor on the dash panel.
These two thin wires are the speed setting instruction to the hedgehog.

On what you have told me I think your new hedgehog is duff as well as the old one.
Unfortunately there are a lot of cheap duff ones being offered on ebay at present.
That is why I keep asking about where you bought it from.

John

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