Heater blower

Car Mechanics (UK) - - Help! -

Q One of my cus­tomers asked me to look at his 59-plate Citroën C5 be­cause his heater blower has stopped work­ing 90% of the time. I can’t find a Haynes man­ual for this par­tic­u­lar year, only for the pre­ced­ing years. My first thought – at the time, the blower didn’t work at all – was the re­sis­tor pack. Af­ter hunt­ing around, I be­lieve I lo­cated it high up on the right-hand side of the pas­sen­ger footwell. I was un­able to de­tach the wiring con­nec­tion as you can’t see it prop­erly, but it seems that you need to dis­con­nect this in or­der to be able to turn the re­sis­tor pack to ex­tract it. I tried tak­ing out the glove­box for eas­ier ac­cess, but even af­ter un­do­ing ev­ery screw it re­fuses to budge!

Af­ter this, the blower started fir­ing up, but soon stopped again. You op­er­ate the air-con­di­tion­ing and blower via but­tons rather than a dial and it seems to be an in­te­grated en­vi­ron­men­tal sys­tem rather than the old-fash­ioned way of do­ing things. Mark Boundy

A The prob­lem may well be the rheo­stat, but it could also be that the mo­tor is suf­fer­ing from worn brushes or cor­roded bear­ings. As the mo­tor does op­er­ate oc­ca­sion­ally, it may be pos­si­ble to check this by giv­ing the vis­i­ble end of the mo­tor a sharp tap while the en­gine is run­ning and the mo­tor is turned on. If this prompts the mo­tor to start ro­tat­ing, it is likely to be the mo­tor and not the rheo­stat at fault. It’s also pos­si­ble that the prob­lem is due to a fuse­box con­nec­tion, so a quick check of the fuses to en­sure they are in good con­di­tion would be worth­while.

If the rheo­stat is to blame then the glove­box will need to be re­moved to get ac­cess. The glove­box should be held in place by 10 screws – three along the base, five around the in­ner lip of the glove­box hous­ing (three across the top and one each side) and two screws to­wards the back. Be­fore the glove­box is re­moved you will need to dis­con­nect the glove­box light and the air-con­di­tion­ing in­put. You will also need to de­tach the pas­sen­ger airbag switch – to do this the bat­tery should be dis­con­nected be­fore you start.

With the glove­box out, you should be able to ac­cess the rheo­stat and, by turn­ing it a quar­ter-of-a-turn, it should lift out. It is a fid­dly job and, hav­ing been sit­ting in the top of the heater for a while, it may be tight to turn.

One other point to check is the con­di­tion of the bat­tery and charg­ing sys­tem. The com­plex econ­omy mode sys­tem in the C5 will pre­vent the blower from work­ing if the bat­tery volt­age is too low.

The elec­tronic Citroën rheo­stat unit.

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.