Blower Fan
- Thread starter finny12
- Start date
I have since checked with another Citroen C5 a 2001 model when the motor is running an aircon on the fuses under the bonnet gets power to it mine doesnot get any power to it so I know there is a fault somewhere or broken wire but where it is a probably will be very exspensive fix
Hi Finny
No experience with C5, but I have a Xantia (predecessor of C5) & a Pug 406 (close relative). In the Xantia I had problems with the cabin blower fan, and with the 406 the Air con stopped working.
In both cases the problem lay in the ignition switch - it appears PSA designs allow too much current to be drawn through it. In the case of the 406 the contacts inside the switch did not even look burnt, but dismantling, cleaning and reassembling fixed the problem for a while. When it failed again I replaced the switch (still didn't look damaged), and have had no further problems. In the 406, the LCD screen would indicate whether the air con control was in the "on" or "off" position, but it didn't mean it was working
.
The ignition switch is relatively easy to access, and in later designs like the 406 and (hopefully) C5, replacing the switch does not mean getting a new ignition lock/barrel & key.
Cheers
Alec
No experience with C5, but I have a Xantia (predecessor of C5) & a Pug 406 (close relative). In the Xantia I had problems with the cabin blower fan, and with the 406 the Air con stopped working.
In both cases the problem lay in the ignition switch - it appears PSA designs allow too much current to be drawn through it. In the case of the 406 the contacts inside the switch did not even look burnt, but dismantling, cleaning and reassembling fixed the problem for a while. When it failed again I replaced the switch (still didn't look damaged), and have had no further problems. In the 406, the LCD screen would indicate whether the air con control was in the "on" or "off" position, but it didn't mean it was working
.The ignition switch is relatively easy to access, and in later designs like the 406 and (hopefully) C5, replacing the switch does not mean getting a new ignition lock/barrel & key.
Cheers
Alec
I suspect the car is earlier than the diagrams above suggest. The blower control changed with the facelift cars and the clue might be in the shadow car in addo's diagrams. Early cars had 6 wires on the control modules in 2 green plugs. The same system is used in early C3 too. Facelift (S2 from 2005) cars do not seem to have the same issues with the fan module.
So, the blower works and you do not think you have 12V at the module in the footwell. The 2-way green connector at the module should have permanent earth on pin 2 (via earth MC32 - common and somewhere below the BSI) and switched 12V is at pin 1. The blower motor connects via pins 3 and 4 at the 6 way green socket. I'm not sure of the polarity, but I would guess pin 2 may be the -ve and think you could test the blower wiring from the module socket by unplugging and applying 12V across these pins. Pins 5 and 6 of the 6 way green are from the dashboard A/C control panel and control the fan module.
The 12V supply to the module is switched via the engine slave unit, variously known as BSM, PSF1, BM34, engine fuse/relay box etc.. There are numerous wiring diagram variations, but I am referring to one intended for the RHZ HDi wagon with full auto A/C and automatic transmission. It's probably typical of the others in relation to the blower control. Supply to the blower module is via fuse 18 and this comes directly from the battery +ve. Do you have 12V at both sides of this fuse. F16 is on the same bus from the battery, so you must also have 12V there or there may be a fault inside the BSM. F18 controls a relay, R3, which in turn feeds to pins 8 and 16 of the 16 way green socket on the BSM. You need to see if this is working. If the relay is not operating, then either relay has failed or there is a problem in the BSM or possible the BSI control of the relay. That then becomes an electronic rather than an electrical issue because it's partly a multiplexed control system. The relay will be encapsulated and not easily replaced separately.
I can post you a spare control panel if need be. The BSM is not VIN-coded like the BSI, so can be swapped from another car the same as a test.
I may be able to scan the diagram later, but it is #80.17 in the 2001 listing if you have it on Sedre addo. doc D3AR23NR.
So, the blower works and you do not think you have 12V at the module in the footwell. The 2-way green connector at the module should have permanent earth on pin 2 (via earth MC32 - common and somewhere below the BSI) and switched 12V is at pin 1. The blower motor connects via pins 3 and 4 at the 6 way green socket. I'm not sure of the polarity, but I would guess pin 2 may be the -ve and think you could test the blower wiring from the module socket by unplugging and applying 12V across these pins. Pins 5 and 6 of the 6 way green are from the dashboard A/C control panel and control the fan module.
The 12V supply to the module is switched via the engine slave unit, variously known as BSM, PSF1, BM34, engine fuse/relay box etc.. There are numerous wiring diagram variations, but I am referring to one intended for the RHZ HDi wagon with full auto A/C and automatic transmission. It's probably typical of the others in relation to the blower control. Supply to the blower module is via fuse 18 and this comes directly from the battery +ve. Do you have 12V at both sides of this fuse. F16 is on the same bus from the battery, so you must also have 12V there or there may be a fault inside the BSM. F18 controls a relay, R3, which in turn feeds to pins 8 and 16 of the 16 way green socket on the BSM. You need to see if this is working. If the relay is not operating, then either relay has failed or there is a problem in the BSM or possible the BSI control of the relay. That then becomes an electronic rather than an electrical issue because it's partly a multiplexed control system. The relay will be encapsulated and not easily replaced separately.
I can post you a spare control panel if need be. The BSM is not VIN-coded like the BSI, so can be swapped from another car the same as a test.
I may be able to scan the diagram later, but it is #80.17 in the 2001 listing if you have it on Sedre addo. doc D3AR23NR.
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I'm on subscription, so reluctant to spend another $8.50 without more reciprocity in the quest.
The car I put up was a facelift diesel wagon, from memory. 76774259
The car I put up was a facelift diesel wagon, from memory. 76774259
I have the paper diagrams with updates to about 2003, so I'll try to scan it later or at least the relevant parts of it. The pin information should be a good start at any rate.
The facelift cars never had the same meltdowns as the early cars. They fixed quite a few little issues and sometime in S2 production also changed from CAN-VAN to CAN-CAN, which means the car is connected quite differently.
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I thought Finny's car was an early facelift, that was why I posted the diagrams I had.
First of the facelift cars arrived at the start of 2005, so it could be just on the cusp. However, if it's an 'early' facelift HDi, it will be a 2.2HDi 4HX wagon, not a 2.0HDi RHZ. He can check the VIN and confirm.
Sorry Addo as I said not having any electronic expertise I have no idea where to start my self Thankyou for your help has been greatfully accepted I am giving you as much information as I can that I know of with this issue
Finny,
If I were doing the troubleshooting on my car and had got to this stage, I would try a brief application of fused 12 volts to the fuse and see if the fan starts up. At least that will tell you if you are on the right track.
Cheers, Ken W
If I were doing the troubleshooting on my car and had got to this stage, I would try a brief application of fused 12 volts to the fuse and see if the fan starts up. At least that will tell you if you are on the right track.
Cheers, Ken W
How old is the battery and is it large enough? A battery might look superficially OK and show a voltage with no load, but a failing battery can explain many faults in a C5. Have you had it properly load tested? If the voltage is low, items like the A/C may be disabled for that reason.
Just to add to this historic thread, my findings yesterday after blower fan had stopped. Our Carlo5 has had the typical resistor pack swapped twice (well once repaired) and the harness replaced and been working well through summer.
Found A/cond was actually still running but no fans running at any speed?
Checked the 40A fuse in the BSM (engine bay fuse box) to find the fuse completely melted and the socket completely deformed from fuse not burning out?
What ever relay or tracks lie beneath now damaged beyond repair at my guess.
Anyone in Bris wreaking a Mk1 C5
, will check the happy scrappy in Willawong hopefully still holding onto 1 or 2?
Found A/cond was actually still running but no fans running at any speed?
Checked the 40A fuse in the BSM (engine bay fuse box) to find the fuse completely melted and the socket completely deformed from fuse not burning out?
What ever relay or tracks lie beneath now damaged beyond repair at my guess.
Anyone in Bris wreaking a Mk1 C5
, will check the happy scrappy in Willawong hopefully still holding onto 1 or 2?
One mentioned 40A fuse, melted not burnt out?