is the delaer right? - temp sensor

[danb]

I have the common LCR, temp gauge light flashing in the cold mornings of this week.
I searched and read about the green/black sensors in the expansion tank.

Went to my dealer near to my place of work and they said "You need to replace the whole expansion tank, the sensors are molded into it - that's £46 please"

Are they right? or can I just replace the sensor some how?

 

[STEVEO@CYMRU]

i had to change the whole tank on mine as they are molded but this did not stop the light in the end i had to change a temp sensor on the passenger side of the engine(it was fitted into a housing that was attached to a coolant pipe)


steveo

 

[danb]

i had to change the whole tank on mine as they are molded but this did not stop the light in the end i had to change a temp sensor on the passenger side of the engine(it was fitted into a housing that was attached to a coolant pipe)


steveo

I presume the second repair was cheaper?? If thats the case do you think I should try that first? Or can the dealer tell via diagnostics which needs doing?

 

[Mitchy]

Youve got it slightly mixed up.

The green/black sensor fault lights up the engine warning light and is another fault. The black sensor needs to be replaced for the green.

Your fault (early morning beeps) is a seperate fault and yes the dealer is correct, the expansion tank needs replaced. It has nothing to do with the actual sensors moulded onto it, you need the whole expansion tank replaced

Is the £46 a fitted price? The actual expansion tank costs around £15 and the coolant £5

Hope that clears things up There a 2 different common faults related to the engine coolant temp on the 1.8T

1. The expansion tank (early morning beeps)
2. Engine light on (black to green sensor swap)

The engine coolant temp sensor is no where near the expansion tank though, its located on the other side of the engine

You'll know which 1 you have got though as if you dont have a permanent engine warning light its the expansion tank, if you have a permanent engine warning light and the code is read as a coolant system fault it is the black temp sensor. Yours is obviously the expansion tank fault

 

[danb]

Youve got it slightly mixed up.

The green/black sensor fault lights up the engine warning light and is another fault. The black sensor needs to be replaced for the green.

Your fault (early morning beeps) is a seperate fault and yes the dealer is correct, the expansion tank needs replaced. It has nothing to do with the actual sensors moulded onto it, you need the whole expansion tank replaced

Is the £46 a fitted price? The actual expansion tank costs around £15 and the coolant £5

Hope that clears things up There a 2 different common faults related to the engine coolant temp on the 1.8T

1. The expansion tank (early morning beeps)
2. Engine light on (black to green sensor swap)

The engine coolant temp sensor is no where near the expansion tank though, its located on the other side of the engine

You'll know which 1 you have got though as if you dont have a permanent engine warning light its the expansion tank, if you have a permanent engine warning light and the code is read as a coolant system fault it is the black temp sensor. Yours is obviously the expansion tank fault

thanks for clearing this up for me Mitchy - Yes it is a fitted price.

 

[panholio]

Mine had the flashing temp light fault, the delaer claimed no fault was recorded and topped the coolant up a bit, it's gone now. I'll wait for it to come back.

Check your levels.

 

[g60jet]

Mine had the flashing temp light fault, the delaer claimed no fault was recorded and topped the coolant up a bit, it's gone now. I'll wait for it to come back.

Check your levels.

beeps mean coolant is low on a cold engine from my experiance. check the coolant level first, add a tiny amount of water if its low until the light goes off. (you will need to cycle the igntion to reset it) that way if you have a leak the warning will be back on in no time. Most common casue of leaks on VAG engines if the expansion tank lid on older models where the top is tightened to the max. (newer ones only do up so far). and the second it the water pump starts to leak. although i would only expect higher models. Engine temp sensors can be checked with a multi meter, measuring the ohms across two termials. however im not sure what the valuse should be on the LCR

 

[Mitchy]

Mine had the flashing temp light fault, the delaer claimed no fault was recorded and topped the coolant up a bit, it's gone now. I'll wait for it to come back.

Check your levels.

Even when the level is fine the morning beep is still prone to coming on, but your right sometimes a low level situation can set the light off, although i did think a low level warning light flashed up red, not amber!

I understood it to be...

Amber flash meaning expansion tank at fault.
Red flash meaning low coolant level

However these are not faults as such, so not logged in ECU and no engine warning light

As said before engine warning light is down to temp sensor

 

[StuLCR52]

ok im gonna be dumb here, ive got the red flashy im too cold in the morning to give a **** that ur coolant level is fine light! so i need to replace the whole expansion tank? wud i be correct ?

stu

 

[Mitchy]

If the red light flashes it probably means you need to top up with coolant.

If your coolant level is fine, then yes you need to change your expansion tank.

 

[carlt69]

my LC was having the problem everymorning, light would flash and it would beep when the engine was cold. Went to the dealer and they said there was some corrosion on the sensor and they cleaned it up!!??

It hasn't done it at all since.