Low Coolant Light Woes

[Wychall]

As Max Bygraves used to say, "Let me tell you a little story!"

All of my instruments were working fine, but I didnt have a rev counter. So I sourced a suitable donor unit (very lucky as it needed to be a 5 cyl instrument). Now the fuel and temp gauges on the original clock were different so I used the gauges which came with the rev counter. All went well until I found that the low coolant light is permanently flashing.

I have done all the usual checks (yes there is water in there etc.) and still have the flashing light. I therefore got technical and followed the guide on here by MidLifeCrisis to change the capacitor in the temp gauge. Well blow me down, the light is still flashing. I then got the old gauge out and wired it in parallel with the replacement gauge. The light keeps flashing on the replacement gauge but works correctly on the old one.

Perhaps it is my skill in fitting the new capacitor? Out with the gauge again, remove the replaced capacitor and replace it with another new one. Still flashing!!!!

OK you wizards out there. What do I do next?

[dave friday]

Did you fit the capacitor the correct way round?

[MidLifeCrisis]

Have you tested the gauge with just the 12v and gnd connected (i.e. without the sensor wire connected)? What did it do?
Does the needle on the gauge work correctly?
Bit of a faff - but does the gauge work if you remove the capacitor? (note that the initial 'flash-test' won't happen but the led should flash when the gauge is showing hot, or the coolant is low)

[Wychall]

Thanks for the replies. Yes, the capacitor is the right way round. Double, treble and quadruple checked, at both fittings

I have only had the gauge connected in-situ, hence all connections made. The temperature gauge is working correctly, it is only the continual flashing that is the problem. I will have to dig in again and try removing the capacitor. I can also then check as to whether the innards of the good gauge will fit inside the casing of the faulty gauge.

Or disconnect the LED completely

[bigherb]

Try unplugging the low coolant control relay in position 5 there are two part numbers for SA models it may be incompatible.