HI

 

IVE JUST ACQUIRED A 2000 PLATE FABIA 1.4MPI 8 VALVE WITH 23.000 MILES ON THE CLOCK

 

START, RUNS AND DRIVES SPOT ON.

 

THE ISSUE IM HAVING IS WITH THE TEMP GAUGE AND THERE IS A VERY VERY FAINT FLASH TEMP WARNING LIGHT AS IF THERE IS A BAD EARTH

 

. WHICH SENSOR CONTROLS THE TEMP GAUGE AS IT WORKS INTERMITTENTLY ?

 

I  HAVE A SNAP ON SOLUS PRO DIAGNOSTIC MACHINE WITH INDICATED FAULTY TEMP SENSOR (TOO HIGH)

 

I HAVE SWAPPED THIS AND THE FULL THERMOSTAT HOUSING (WHICH WAS BROKEN INSIDE) AND ALSO THE EXPANSION TANK FOR GOOD MEASURE

 

THIS HAS MADE NO DIFFERENCE AT ALL

 

I CAN TELL BY THE DIAGNOSTIC MACHINE THAT IT IS RUNNING AT THE CORRECT TEMP AND FANS CUT IN AND OUT AS THEY SHOULD IM PRESUMING THAT IF THE SOLUS PRO IS SHOWING THAT THE TEMP IS RUNNING AT NORMAL TEMP THAT THE SENOR IS OK UNLESS IT GETS A READING FROM ANOTHER SENSOR

 

IF I CLEAR THE FAULT IT RETURNS STRAIGHT AWAY AND THE TEMP GAUGE DOESN'T MOVE

 

IF I UNPLUG THE SENSOR ON THE T-STAT IT SHOWS THE SAME FAULT

 

IF I UNPLUG THE SENSOR ON THE RAD IT SHOWS THE SAME FAULT

 

SAME ON THE EXPANSION TANK

 

IF I JUST UNPLUG THE SENDER ON THE RAD .CLEAR THE FAULT THE GAUGE WILL RISE TO NORMAL TEMP FOR ABOUT A SECOND THEN FALL AGAIN AND THE CODE WILL COME BACK.

 

IVE NOT DRIVEN IT SINCE SWAPPING THE PARTS AS I WANT TO GET TO THE BOTTOM OF THE PROBLEM BUT BEFORE SOME TIMES THE GAUGE WOULD READ NORMAL , SOMETIMES NOTHING THEN IF YOU TURNED IT OFF AND ON AGAIN IT WOULD READ NORMAL.

 

.THE WATER IS CIRCULATING, EVEN TEMP ACROSS THE RAD , NO LEAKS . NOTHING

 

DO I SWAP THE RAD SENSOR OR DOES THAT JUST CONTROL THE FANS ? (WHICH DO CUT IN AND OUT AS THEY SHOULD)

 

ANY ADVISE WOULD BE APPRECIATED

 

CHEERS RUSS

 

Yes, the radiator thermoswitch only controls the fans.

HI

 

I THOUGH IT DID BUT THANKS FOR CONFIRMING IT

 

CHEERS RUSS

The sensor in the thermostat housing is read by the engine ECU, which then talks to the dash instruments module to drive the gauge.  The warning light is coolant level, controlled by the sensor in the expansion tank, possibly also acting as an overheat warning according to what the engine ECU is reading form the sensor on the thermostat housing, not sure about that last one though.

 

Older Mk1 Fabias sometimes suffer with cracked solder joints on the 32-way green connector on the back of the cluster circuit board.  This can cause all sorts of issues, but can be quite easily repaired by re-flowing the solder joints.

THAT WOULD MAKE SENSE AS THERE IS OBVIOUSLY A READING GOING TO THE ECU FROM THE SENSORS, IT THERE ANYTHING ELSE I CAN CHECK BEFORE PULLING THE CLUSTER OUT ?

Christ, my ears are ringing, can you turn caps lock off please.

 

Do what Wino suggests, it's the instrument cluster, or you could just ignore it and drive the car.

Hi , sorry about the cap locks if it offends .The shift key is not very good on my laptop so easier to stay on caps lock  i will investigate the cluster . i don't like driving without gauges especially temp gauges.

Thanks Russ

On ‎6‎.‎1‎.‎2017‎ г. at 18:38, Wino said:

Older Mk1 Fabias sometimes suffer with cracked solder joints on the 32-way green connector on the back of the cluster circuit board.  This can cause all sorts of issues, but can be quite easily repaired by re-flowing the solder joints.

 

Precisely. Similar problem on my daughter's Mk1 2003 with temp light and fuel gauge erratic reading. Replaced (twice) the expansion tank with no success. Thanks to Briskoda forum advice finally fixed the issue with re-soldering  32 green connector and particularly right bottom 2 pins (instrument cluster circuit board view from backside). BTW connector soldering looks perfectly good but apparently it is not so do re-solder.