Megane 2 fault codes

[felloffajetski]

Hi all,

Have a 57 plate 1.5 DCI Megane Sport tourer, 86bhp, 170,000 miles on it and still going....

I have recently replaced the coolant temp sensor as temp gauge was not going above first line, Its now throwing up error codes:

-P0670
-P0115

The coolant temp is reading -40 celcius on my diagnostics so believe that accounts for one of the fault codes, am i right in thinking its a faulty temp sensor??

The other code I believe is to do with glow plugs, so i must have some defective plugs that need changing, is that correct?

Other than the fact the 'check injection' is lit which i believe is due to the erroneous coolant temp reading, she runs fine.

Thanks for your help

[tomalamix]

hy there,

the check injection and that fault code means that probably one or more glow plugs are shot, there is a thread here that shows how can you check which one are faulty.

For the temperature sensor its a little bit more tricky because you said you've changed the coolant temp sensor one time and it seams to be with the same problem.

do you have access to the old sensor, fit it and read live data to see the temp reading?

[felloffajetski]

hi,
thanks for reply,

sorry, yea the original temp sensor was working but it would not go above first mark on gauge and struggled to start when cold (glowplugs probably)

so i replaced with new, and now getting -40 celcius on diagnostics. it holds glow plugs on for a long time before engine starts.

I have the old sensor so was going to reconnect and then see what it reads so i know its just a faulty new temp sensor (it was cheap....)

thanks

[tomalamix]

Did you change the temp sensor or the whole thermostat that includes the temp sensor?

[felloffajetski]

Hi,

Just the temp sensor.

I plugged the old one back in and it reads 14 celcius on diagnostic, car air temp was reading 10 celcius. Am starting to think sensor was ok, perhaps the thermostat needs replacing?

Im going to reinstall the old sensor??

[felloffajetski]

hi again,

so put old coolant sensor in and car back to normal (ish)

on obd i witnessed coolant temp rise to 66 - 67 celcius then drop down to low 60's - thermostat must be opening early hence running cool.... then again fault code still exists reference p0115 coolant sensor low circuit 1 (or thereabouts) so does this point back to faulty temp sensor ?????

i took apart boot wiring where it goes from car into bootlid as we have had issues with boot opening randomly and found several wires split. i reconnected these and wrapped up as best as possible,

this morning my wife tried to start car and it lit up with brake fault, steering fault, lights turned on by themselves, wipers going, and the wife could not turn off the engine so i told her to stall it which she did, but lights would not turn off and engine fan was going flat out...... (issues with keycard also occuring for a while with it not being recognised easily)

would a flat battery cause this? or is it water in fuse box? or ecu? I have recently done coolant sensors and been disconnecting ecu (behind battery if it is ecu), firstly disconnecting battery, could this cause issues?

so anyhow, rac called out, and after investigation battery is charging ok, he reset ecu and since then its been ok. it starts ok, stops on button, and no christmas tree lights on dash. ?????

confused. starting to think might have to get rid as it seems in the last few months electrical gremlins have been working there way in.... and she is on 170,000 miles!!

anyone any ideas???

[tomalamix]

its better to check the uch for water ingress, if its totally dry, and if everything is ok post back to keep going on the sensor

good luck