Coolant Gauge/light Sensor Wires

[DanRM 0 1 Cars]

My coolant gauge hasn't worked since getting the head gasket done a few months back, hasn't really bothered me till now where i'm using the car more often and fed up with not being able to see how hot it's running.

 

I asked for the coolant sensor to the gauges and not for the ECU when I last went to my parts shop and they gave me a Green coloured double connector sensor which to me sounds like the ECU one as it looks just the same as the blue one I got when I changed that. Now that I have a few days off work I was going to take the single spade sensors out to take to them so they can see properly, but in doing so I was wondering is it possible that the guy who did the HG put the wrong wires on each sensor.

 

I have no idea what would happen if they were swapped but at the moment the warning light works on ignition but the gauge doesn't read anything after the engines hot where as before the work was done the gauge was spot on. So could this possibly be the problem? Thought I'd ask before spending any more money on it

 

Cheers

[Vili 17]

Try swapping the wires with each other. They usually never go right the first time after they've been disconnected. (Well at least when I'm under the bonnet.)

[pug_ham 241 3 Cars]

If the sender gauge wires are cross connected you should find the red temp warning light will be glowing dimly.

 

If you still have the original wiring, the wires are coloured red & green with coloured plastic covers that relate to the sender, iirc red to the smaller sender & green to the larger of the two.

 

g

[Anthony 1,000]

Check the actual wiring too, as typically it's in very poor condition these days and phone to breaking or suffering poor connections on the under bonnet brown multiplug.

 

Easiest test is to short the plug to the engine block, which should make the gauge read maximum or the warning light come on depending on which wire it is.