renault traffic 1.9 dci glow plug light stays on all the time we,ve changed egr valve,boost pressure sensor and vaccum sensor any ideas

andy, September 2010

finally sorted. Replaced the UCH - coded multiplexer that allows electrical circuits to share cabling. Another Renault idea that is great until it fails. Problem started with the UCH getting water damage.

J Main, October 2010

Andy, further to my last, I should say that I tried and failed miserably to access the ECU. I couldn't figure out how to get into the steel cover. Anyway prior to opening the fuse box I disconnected the battery - just in case. All the plugs and fuses were taken apart, cleaned and reinstated. Be aware of course that you'd need your radio code in order to get that operational again after disconnecting the power. A hair drier aimed at the fuse box would possibly be a good idea - there being no more warm summer days around. I'm now going to make a waterproof cover for the fuse box / ecu box.
Plse let me know how you get on.

John M, September 2010

Hi Andy
I had similar type problem which was fixed by clearing the fault codes (and replacing sensors unneccessarily in my view). And now just had half my electrics fail - the common link seems to be rain (or possibly pressure washing). It looks like water might be getting onto the terminals in the fuse box under the coolant tank. After a good dose of WD40 the fault came and went and has now settled down back to normal after about 3 hours - supporting my theory that the connections need drying out.

John M, September 2010