Rear Washer

[LEEHUMP1]

Hi my rear washer does not work on my 2003 C5 Estate, the front works fine. I cannot hear the motor running for the rear but can for the front. I understand both front and rear work off the same pump which attaches to the washer bottle. I today took the nsf wheel off and removed some of the wheel liner to have a good look. I can see the washer bottle which is black (I was expecting it to be white like most other cars). I can see the washer bottle motor which has both pipes running off it which I need to replace. There is also another electrical connector attached to the bottle which is nearer to the wheel. Is this the low screenwash level sensor?

[myglaren]

Hi my rear washer does not work on my 2003 C5 Estate, the front works fine. I cannot hear the motor running for the rear but can for the front. I understand both front and rear work off the same pump which attaches to the washer bottle. I today took the nsf wheel off and removed some of the wheel liner to have a good look. I can see the washer bottle which is black (I was expecting it to be white like most other cars). I can see the washer bottle motor which has both pipes running off it which I need to replace. There is also another electrical connector attached to the bottle which is nearer to the wheel. Is this the low screenwash level sensor?

It is indeed.

I'd suspect a break in one if the leads that power the pump, or corroded terminals, if it runs in one direction and not the other.
A multimeter would show which one.

[citro6hydra]

Hi, the washer pump is a permanent magnet type motor which means it can be made to run either clockwise or counter clockwise simply by reversing the supply voltage polarity and by using a two outlet system the pump will supply water to either the front or rear washers.
Your first check should be to see whether the voltage at the pump does reverse in polarity when changing from front to rear wash, it is possible that some internal fault in the pump could cause this, but unlikely. The fact that the pump runs ok for the windscreen eliminates cabling / connectors / as a fault.

The two white wires which supply the pump are coded 510 and 530 they go back to pins 14 and 11 on the fusebox connector then to two spdt {changeover} relays within the fusebox which provide the polarity reversal. These are controlled by some electronics which are linked to the BSI unit and washer stalk etc.

To go any further with fault finding and I'm not sure that lexia can assist with the fine detail, and fusebox repair is getting into realms of electronics and although the two relays can be replaced if faulty it is a specialist job.
Hope this assists.