Temp gauge woes

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m_jermyn
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Post Sun Aug 09, 2009 2:35 pm

Ok so I had the battery disconnected the other day cleaning out the boot compartment whilst checking for water leaks (all fixed finally). Gave the car a good wash and on the way home I noticed I had no temperature showing. Bit off a concern as its in need of a fan clutch (which has been ordered and on the way).

Now when I turn on the ignition the needle goes up but stops just under the blue and wont rise. When ignition is switched off she drops to a rest.
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Which one in the temp sensor?
ImageImage

I have done a search and read through a heap off posts and Brianmooooore always refers to the brown/purple wire labeled Number4 in the big plug near the fuse box. Mine isnt brown and purple...... \Image

I have a spare gauge that I can try in it aswell.

Please help

Mike
m_jermyn
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Post Sun Aug 09, 2009 3:21 pm

The time difference here is Australia is going to be a issue solving this as I cant just go try something and report back immediatly. So first thing im going to do is swap the gauge, if that doesnt work what next?

As much info as possible would be great guys.. And in plain english please im not to good with electrics just a lowly panel beater and spray painter.

Mike
stonesie
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Post Sun Aug 09, 2009 4:32 pm

Ok, where you have the screwdriver is the right area, the brown sensor there is the one for the dash the other is for the ecu :)
kundiboy
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Post Sun Aug 09, 2009 7:10 pm

Remove the wire from the brown sensor and usinga small length of wire short it to earth. With the ingnition on this should make the gauge shoot into the red. If this doesn't hapopen then there is either a problem with the wiring to the gauge or the gauge it's self.
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m_jermyn
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Post Mon Aug 10, 2009 6:29 am

1.
Ok I have changed the gauge with a known working one.

2.
I have removed the wire off the sensor and earthed out the sensor wire and also the the sensor itself. The needle still just goes below the blue with ignition on.

3.
I have taken off the top of the big plug thing on the fire wall in photo above next to fuse box and the needle still just goes below the blue.

Whats the next thing to try?

Is this the correct sensor?
Image


Thanks for your patience

Mike
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Post Mon Aug 10, 2009 8:16 am

yes, thats the gauge sensor.

Not sure what else to suggest here. Brian Moore about?
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m_jermyn
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Post Mon Aug 10, 2009 1:55 pm

Thanks Will you a bloody legend will try tomorrow..

I also disconnected the sensor wire and ran another wire from the sensor directly to the C101 plug wire pin (4) effectively cutting out the wiring in the engine bay, got nothing there either.

So what your saying is remove the rubber boot on top of the c101 plug but dont seperate the plug, and ground out wire pin (4) is this correct? Should this make the needle shoot to the red or stay blue? I must do this on both sides of the plug to eliminate the plug itself?

For the second bit you mention pin # 26, I assume pin #26 is a pin located inside the blue plug on the back of the temp gauge, and not pin # 26 in the c101 plug as they only go up to 20

I think I understand. Remove the cluster and disconnect the blue plug, cut the cable tie holding it together, separate the plug and find the brown/white wire which should be pin #26 Put a thin wire in pin #26, reassemble the blue plug, plug it back in and earth the thin wire with ignition on. This should make the gauge jump to red.

Is that right?

If this dont work I need a new CI board..

Thanks again mate and NZ is where we send the people that are shit at sport. :flipbird:

Mike
m_jermyn
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Post Mon Aug 10, 2009 2:50 pm

Just a thought could it be the sensor itself?
Grrrmachine
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Post Mon Aug 10, 2009 4:12 pm

The idea of shorting out wires without having the sensor connected is to isolate the sensor from the fault list. The sensor is basically a variable resistor, whose resistance decreases with heat. If you bung a solid wire across where the sensor SHOULD be, resistance = 0, meaning the guage should register in the red. If it doesn't, it can't be the sender, and must be the loom of the guage itself. If it's not the sensor, and it's not the guage, it's either the loom or the whole cluster.
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Brianmoooore
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Post Mon Aug 10, 2009 7:55 pm

It's very possible that you're all chasing aquatic birds of a non domestic variety!
Car battery was disconnected - SI board batteries just clinging to life, finally turn their toes upwards!