Club 80-90 Forums

MidLifeCrisis wrote: picture as a reference

ghost123uk wrote:

MidLifeCrisis wrote: picture as a reference

Good picture/diagram Where did you find that, or did you do it ?

MidLifeCrisis wrote:OK - So the story so far is ... (let us know if any of the below assumptions are incorrect)
1) The led flashes all the time that the ignition is switched on
2) The needle of the gauge does work correctly (i.e. it moves slowly up to the approx 12o'clock position when the engine has been running for a few minutes)
3) You had the same symptoms when you changed out the dash pod for a known good one from another van.
4) You've removed the 43 relay and have the same symptoms.

Use the below picture as a reference;


So,
a) if the led flashes with the relay removed then you can discount the coolant level probe and wiring to/from it as a culprit (because with the relay removed all of this is unconnected to the gauge)
b) if the led flashes on the 'known good' dash then you can discount any component of the dash/gauge as the culprit (because the two gauge behave the same)
c) the gauge needle works correctly so we can discount the temperature probe and the wiring from the temperature probe to the dash (because the gauge needle is being 'driven' correctly by the temperature probe as it is heated by the coolant)

(I think) that only leaves the ground wiring to the gauge pod??? Or possibly (but more unlikely) the 10volt supply to the gauge.

So;
1) Have you checked that the ground wire(s) to the gauge pod (in the long white connector that connects to the back of the dash) has a good ground connection?
2) And have you measured the 10volt supply to the gauge to ensure that it is a good solid 10volts??

jrt wrote:^^^^^^^^^ sounds like good advice. Just had a search on t'internet, someone with a similar problem resolved it by cleaning the connections behind the guage tightening the brass retaining nuts then running an earth to the van body from the negative terminal.
David

pfield69 wrote:My checks so far.

Voltage reg = 9.9v
continuity checked ok from red/yellow cable #6 to gauge terminal nut
continuity checked 300kohms to earth from #5 of relay34 or 0ohms when coolant level plug jumped with wire.
Good earth on pin#3

What resistance should be on the temp sender?
Relay 43 removed still makes light flash.