Xantia Heater Fan Stays On Full Blast!!
Moderator: RichardW
Xantia Heater Fan Stays On Full Blast!!
Hi All.
Wonder if anyone can help. 2000 HDI Xantia.
Put Heater fan on full this morning to move frost. Turned it down and it just stays full on!! IE it wont turn off at all. The sliding knob does not do anything!
Can anybody tell me the likely cause and what I can do?
Am at present puting the fuse in and out!! Its always really hot, or really cold in the car!!
Really appreciate any help.
Thanks.
Wonder if anyone can help. 2000 HDI Xantia.
Put Heater fan on full this morning to move frost. Turned it down and it just stays full on!! IE it wont turn off at all. The sliding knob does not do anything!
Can anybody tell me the likely cause and what I can do?
Am at present puting the fuse in and out!! Its always really hot, or really cold in the car!!
Really appreciate any help.
Thanks.
Squirrels are natures little speed bumps.
Transistors MJ11015
The original transistors are, of course, unavailable.
The replacements are MJ11015.
The replacements are MJ11015.
2002 C5 2.0i AL4 230,000 km 76372389
-
- Moderating Team
- Posts: 11563
- Joined: 02 Apr 2005, 16:11
- Location: Charmouth,Dorset
- My Cars: Currently:
C5 X7 VTR + Satnav Hdi estate Silver
C5 X7 VTR + Hdi Estate 2008 Red
In the past: 3, CX td Safaris and about 7, XM td estates. Lovely cars. - x 1199
Thanks clogzz, someone else was asking about them yesterday and I couldn't remember, I'll make a note of that.
vagabond - The transistors are riveted to a plate on the motor, If I remember correctly, you have to remove the motor from its housing by compressing the three rubber blocks around the circumference, you will then see the transistors. Unsolder the leads, two on each,make a note of their positions, drill out the rivets, fit the new transistors with suitable nuts and bolts, and resolder the wires.
vagabond - The transistors are riveted to a plate on the motor, If I remember correctly, you have to remove the motor from its housing by compressing the three rubber blocks around the circumference, you will then see the transistors. Unsolder the leads, two on each,make a note of their positions, drill out the rivets, fit the new transistors with suitable nuts and bolts, and resolder the wires.
A darlington pair transistor is also a standard bi-polar transistor. Difference is that a darlington pair has 2 transistors in series (hence the designation) to decrease the required base terminal current drive. This in turn makes for double the base-emitter forward bias voltage - as you in effect then have 2 forward biased diodes in series.
In such a "simple" application as this fan speed controller, the difference does not mean anything to the function.
In such a "simple" application as this fan speed controller, the difference does not mean anything to the function.
Anders (DK) - '90 BX16Image
-
- Posts: 449
- Joined: 28 Sep 2003, 11:08
- Location: North West UK
- My Cars:
-
- Moderating Team
- Posts: 11563
- Joined: 02 Apr 2005, 16:11
- Location: Charmouth,Dorset
- My Cars: Currently:
C5 X7 VTR + Satnav Hdi estate Silver
C5 X7 VTR + Hdi Estate 2008 Red
In the past: 3, CX td Safaris and about 7, XM td estates. Lovely cars. - x 1199
Anders - Thanks for the info for the transistors, I knew the configuration of the darlington pair but not how it would work in this application.
BonceChops - I have only just learnt of this new 30 amp rated transistor from clogzz, but I have always used 15 amp rated transistors in the past with no problem, I certainly have not had them fail again. The old 2N3055 is almost indestructable, so I would think they would be OK.
BonceChops - I have only just learnt of this new 30 amp rated transistor from clogzz, but I have always used 15 amp rated transistors in the past with no problem, I certainly have not had them fail again. The old 2N3055 is almost indestructable, so I would think they would be OK.
Transistors
Hello all,
As it happens, the original transistors FW26025A1 are darlingtons, rated at 20 A.
I get my stories from Planète Citroën Forum, where I got this:
FW26025A1 sont des PNP Darlington Vce=100V Ic=20A Pdisp=160W
MJ11015 sont des PNP Darlington Vce=120V Ic=30A Pdisp=200W
No idea as to what the current is at maximum speed.
There also has to be allowance for higher than normal current when the pollen filter is very dirty.
The blower motor fuse is 30 A.
As it happens, the original transistors FW26025A1 are darlingtons, rated at 20 A.
I get my stories from Planète Citroën Forum, where I got this:
FW26025A1 sont des PNP Darlington Vce=100V Ic=20A Pdisp=160W
MJ11015 sont des PNP Darlington Vce=120V Ic=30A Pdisp=200W
No idea as to what the current is at maximum speed.
There also has to be allowance for higher than normal current when the pollen filter is very dirty.
The blower motor fuse is 30 A.
2002 C5 2.0i AL4 230,000 km 76372389
I don't think indestructable is quite the right word for the 2N3055/2N2955..... I've lost count of how often I've replaced those things in things like regulated power suppliesPeter.N. wrote:BonceChops - I have only just learnt of this new 30 amp rated transistor from clogzz, but I have always used 15 amp rated transistors in the past with no problem, I certainly have not had them fail again. The old 2N3055 is almost indestructable, so I would think they would be OK.
If you want something a bit more indestructable, try something like the MJ802/MJ4502, specifically designed for medium voltage high current applications like linear regulators. 90 volts, 30 amps, 200 watts, same package. Very rugged transistor in actual fact as well as just in paper specs.
One thing that concerns me a bit though is that if the original transistors are indeed darlington, it may not be a good idea to replace them with non darlington types, without knowing what the driving circuit is like.
The extra base current required either may not be supplied (preventing the fan from going at the correct speeds) or it may even blow up the driver stage. Cavet Emptor....
Edit: Just read Cloggz post, looks like they are darlington, so the MJ11015 could be a good bet...
Regards,
Simon
Simon
1997 Xantia S1 3.0 V6 Auto Exclusive in Silex Grey
2016 Nissan Leaf Tekna 30kWh in White
2011 Peugeot Ion Full Electric in Silver
1977 G Special 1129cc LHD
1978 CX 2400
1997 Xantia S1 2.0i Auto VSX
1998 Xantia S2 3.0 V6 Auto Exclusive
1997 Xantia S1 3.0 V6 Auto Exclusive in Silex Grey
2016 Nissan Leaf Tekna 30kWh in White
2011 Peugeot Ion Full Electric in Silver
1977 G Special 1129cc LHD
1978 CX 2400
1997 Xantia S1 2.0i Auto VSX
1998 Xantia S2 3.0 V6 Auto Exclusive
-
- Posts: 449
- Joined: 28 Sep 2003, 11:08
- Location: North West UK
- My Cars:
When almost at full speed a relay operates on the speed control board that shorts the collectors and emmiters so no current is conducted through the transistors.AndersDK wrote:The MJ11015 is rated at 30Amps - whereas the MJE2955 is rated at 15Amps. It will pop out first time you set the fan at full blast.
The relay coil is connected between the transistor base and +12 volts. The driver circuit must be capable of supply enough current to operate the relay. Would the current needed to energise the relay coil be more or less than the base current of the non-darlington type transistors.Mandrake wrote:One thing that concerns me a bit though is that if the original transistors are indeed darlington, it may not be a good idea to replace them with non darlington types, without knowing what the driving circuit is like.
I will change mine but they are on a 3-4 week lead time and the MJE2955's were only 80 pence each and in stock.
I had wondered if by fans intermittant running was being caused by too high a base current.
Neil
Now Citrtoenless
Now Citrtoenless
MJ11015
Peter.N. wrote:There you are clogzz, I dont think I will lose them now!
Hello Peter,
The transistors will feel at home in your signature, brilliant idea !
2002 C5 2.0i AL4 230,000 km 76372389