Hi
I have a fiat stilo dynamic 1.6 2004
I am looking for a fiats breakers yard and i am looking for a 4 pin heater blower ..denso number B838 which seems near on imposible to get hold of second hand can any one help please.

Richard

tuckermoto said:

I have checked all fuse,s and all ok.
I have discoverd the relay for the heater circuit T8 has burn damage..
I have replace the relay
I have taken out the heater fan motor
I have checked volts on the supply cable to the heater.( 4 wire plug )
colours of plug wires REd and Black 4mm blue and green 0.5mm
I have tested for voltage from these wires
RED to earth no volts
black to earth no volts
green to earth no volts
blue to earth...1volts to 4.8 volts when turning up the heater controle push button for the fan

Click to expand...

The red wire to pin 4 of the fan motor should have a permanent ignition switched 12v supply from relay T8 and fuse F8. The operating coil of T8 is supplied via fuse F31 in the dashboard fuse box. If you have 0v at pin 4, then your problem is more likely to be with the power supply to the motor than the motor itself.

The black wire to pin 3 of the fan motor is a permanent earth so should be 0v as you've indicated.

The blue and green wires to pins 1 and 2 of the fan motor are control signal and feedback wires from the Climate Control ECU.

tuckermoto said:

I have checked fan motor via stand alone battery connecting to red and black pins of motor and motor does not run

Click to expand...

I fan motor has built in electronic speed regulation controlled by a varying voltage signal sent from the Climate control ECU via the small blue wire to pin 2 of the fan motor. The small green wire at pin 1 of the fan motor provides a feedback signal to the ECU. Connecting a 12v supply and earth directly to pins 4 and 3 of the fan motor will not operate the motor because the control signal will be absent.

You have threads about this issue in Newbie Central and Let's Talk Fiat sections of the forum. NC is just for new members to introduce themselves. LTF is for general issues that are not specific to one model.

Please post any further issues in Stilo section of the forum here: www.fiatforum.com/stilo
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thank you for posting the information on the blower heater wiring it has made fault finding a lot easyer




regards


Rchard

fault now found on heater blower circuit...The fan its self had broken and was jaming in the heater in the housing causing the F31 fuse to blow....now looking for a second hand 4pin heater blower...by the way there was 2....fuses marked up as F31 in different rows in the same fuse box beside drivers steering wheel thats confusing ...

This is how they should be. F31 is at the top left for right hand drive Stilos.
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