coolant and petrol gauges reading low

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Ray
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Location: St Albans, Herts: Syncronaut No 27

coolant and petrol gauges reading low

Post by Ray »

Coolant problems again, temp and fuel gauges reading low ? voltage regulator. Thought I had fixed it by cleaning up connection to the coolant sensor and all was well until the next use when it was the same. Checked all earthing points to the engine end today then noticed that the coolant light does not self test now or come on at all with the ignition. I have a new sensor and a new relay which intend to try but it seems an earth problem really. It happened couple of years ago when I had e steering fitted and was a wire that had no conductivity and Tim S fixed it for me. I will press on with it. It seem odd that the led has packed up completely. Could it be the voltage regulator?
Ray
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AngeloEvs
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Re: coolant and petrol gauges reading low

Post by AngeloEvs »

As both gauges are reading low I would measure the voltage from the regulator. This is usually best done with the dash on a bench but you could do it with the dash in situ if you have a multimeter and set to DC volts..

Remove the dash cover and you should see three nuts that hold and connect the temp gauge to the dash membrane PCB. The centre nut is 0v earth, place the one of the Meter probes on it and the other probe on either of the other nuts but preferably the left one if you are sat on the drivers seat. A reading of 10v is correct.

A low reading could be caused by several problems including the regulator legs badly tarnished and not making good contact in the socket.
1987 DG Karisma LPG with remodelled interior

Ray
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Posts: 246
Joined: 08 Oct 2005, 11:49
80-90 Mem No: 94
Location: St Albans, Herts: Syncronaut No 27

Re: coolant and petrol gauges reading low

Post by Ray »

Thanks for the reply, I will check that. I have a replacement regulator which I found after buying it for the last time it happened but didn't need it as it was a poor earth in the end.
Ray
2.1dj RHD syncro

Ray
Registered user
Posts: 246
Joined: 08 Oct 2005, 11:49
80-90 Mem No: 94
Location: St Albans, Herts: Syncronaut No 27

Re: coolant and petrol gauges reading low

Post by Ray »

Checked voltage at the regulator today and it was 8.3v. So i will change the regulator and try again. I am told that the regulator has to mounted in reverse or upside down as it is a later one. Thanks for the info.
Ray
2.1dj RHD syncro

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