diesel heater exchange element????

Hello i would of put this in diesel engine section as im led to believe by the haynes only the diesels have this secondary heater.
Now the issue arose today on the school run and i was just feeling where the warm air was coming from behind the lower dash passenger side and i caught what i now know as the wiring clamp/cover to the electric heater exchange or as citroen call it the AIR REHEATING RESISTANCE part no 6436a9 and the car started to grumble and moan and chugg so on further investigation the 2nd and 3rd pin on both the element and the plug are quite badly burnt/charred.
now ive had the element out to take a look and the unit itself looks in good condition apart from the connectors being charred.
priced one up on citroen and its £153.05 so i taken a look on ebay and found one for £25.00. so basically before forking out can anyone help me by telling me how to test the unit.
citroen c3 old 53 plate 1.4 hdi lx 118000

MATTHEW LOMAX wrote:can anyone help me by telling me how to test the unit.

I would expect each of the connections to tie up with each of the lengths of metal that run the length of the unit. One extra for an earth. There should be a resistance between each connection and 'earth' (common).



So the test would be for consistent resistance between each heater element connection and the common earth, well that's where I would start

Well its been 2 weeks since the issue, i tested the plug/connector and also tested the heating element cleaned it all up and put it back together.
On doing so discovered that the connector wasn't pushed home correctly. so the only thing i can put it down to is the plug was jiggling about and not contacting the pins properly thus making excessive heat at the pins/plug.
Now we have a blooming warm car. All my wife can say how quick she warms up the cabin now.
so will still be keeping an eye on it but fairly confident its been resolved.
also what puzzled me as there were no securing method for the connector. i.e it doesn't click into place.

MATTHEW LOMAX wrote:Well its been 2 weeks since the issue, i tested the plug/connector and also tested the heating element cleaned it all up and put it back together.
On doing so discovered that the connector wasn't pushed home correctly. so the only thing i can put it down to is the plug was jiggling about and not contacting the pins properly thus making excessive heat at the pins/plug.
Now we have a blooming warm car. All my wife can say how quick she warms up the cabin now.
so will still be keeping an eye on it but fairly confident its been resolved.
also what puzzled me as there were no securing method for the connector. i.e it doesn't click into place.

Great news with the warm cabin.

Maybe a blob or more of Hot Melt Glue would help secure the plug to the socket, yet allow removal if necessary

MATTHEW LOMAX wrote:also what puzzled me as there were no securing method for the connector. i.e it doesn't click into place.

I think you are missing the light grey sliding part of the plug.

The slider locks the plug very tightly and needs to be slid back to release the plug from its socket.


The picture shown the plug with its cover missing, but does include the sliding locking part which is light grey in colour.

this is the slider disengaged