[SierraDan]

Hey hey.
Suzuki Sierra. G13BA. Sound condition cooling system. Factory gauge and sensor.

My gauge decides to have fits on what temperature my car runs at. It chops and changes whether it works or not, so I assume there is a connection loose or something somewhere, but I really have no idea with electrical crap.

At cold it sits just under the red, and as it warms up it moves within the red. I know it runs at temperature because I have an infared temp gun thingo due to paranoia, and I'm pretty convinced its mostly accurate.

Where should I look to fix this as a temporary solution to fitting an aftermarket gauge?

Cheers, Dan.

[Matthew]

Test the resistance of your temp sender.

50°c = 133.9-178.9ohm
80°c = 47.5-56.8ohm
100°c = 26.2-29.3ohm

[SierraDan]

I can only use my tongue. The multimeter is locked in my old boys toolbox.

Its brand new, so I am confident its not the sender.

[atari4x4]

SierraDan wrote:

I can only use my tongue. The multimeter is locked in my old boys toolbox.

window licker version 2.0?

[SierraDan]

atari4x4 wrote:

SierraDan wrote:

I can only use my tongue. The multimeter is locked in my old boys toolbox.

window licker version 2.0?

Nah, I've only got v1.9

[Matthew]

Silly question, but was it working when you put the sender in?

I once ordered a sender from repco, they insisted it was the right sender, they seemed to work on the basis of "it fits, it's the right one"

Testing stuff with a dmm is all I can suggest.

[SierraDan]

It was working when I got the car. Did a service replacing the thermostat and sensor, worked after that. Still works sometimes, but most of the time it reads high.

Its like when you've got a dodgy join on something and sometimes it works, and other times it doesn't.

[atari4x4]

check the body earths from the battery etc.

[SierraDan]

I will when the weather clears up, so don't flame me for this:
But why? Wouldnt that make everything go wonky?

[Matthew]

Try testing the meter while your at it. You don't need a mm

Instructions are in the FSM. Page 21-11

[want33s]

Have you fitted a bigger alternator?
Did you upgrade the power feed cable?

[SierraDan]

Haven't done anything to it yet.

[want33s]

I can't remember the details but (I think it was) Royce posted in an electrical thread something about the supply voltage at the gauges fluctuating and causing false readings.

[shandy92]

Matthew wrote:

Test the resistance of your temp sender.

50°c = 133.9-178.9ohm
80°c = 47.5-56.8ohm
100°c = 26.2-29.3ohm

would that be the same for g16b senders?

[losfer]

check the earth in the back of the cluster

[droverdave]

I will try and explain how it works and hopefully it will give you an idea on how you can try and fix it.

The temp sensor has voltage on one side of it (i think its 12V, not sure if its reduced, but its constand positive voltage), and the other side is connected to the temperature sender.

The temperature sender causes resistance between the guage and ground.

The engine is connected to ground via the ground straps on the engine. These ground straps MUST be in good condition for any resistance based senders to work. any additinoal resistance in these ground straps adds resistance to system, and will give false readings.

One way to test your guage, is take the wire off teh temp sender, and put it directly to ground (ie the engine block), it should go full scale. if it doesnt you have a problem with either the guage, or the grounding of your engine block.

Measuring the resistance of the sendor in a cup of hot water is easy with a ~$10 multi meter and try and get the values given above.

It sounds to me that you either have a loose connection on the sender itself, or somewhere between the guage and the sender.

oh and if you have been supplied the wrong sender, it will be different resistances to temperature, and your guage will show some crazy readings. if it has a part number on it, find it, and find a catalogue to compare it against.

[SierraDan]

Sweet, I will check that, sounds good thanks.

Its not the wrong part, I got it myself and matched number because I mistakenly got the wrong sender in my white zook and it read very cold.

It works properly on occasion, so its the right one, just something funky going on which i assumed to be wiring, and you guys seem to agree.

[Matthew]

shandy92 wrote:

would that be the same for g16b senders?

The Russian autodata manual says they have the same resistance.

droverdave wrote:

One way to test your guage, is take the wire off teh temp sender, and put it directly to ground (ie the engine block), it should go full scale. if it doesnt you have a problem with either the guage, or the grounding of your engine block

That's not quite the right way to do it, you should really have a bulb in line, as described in the fsm.

[losfer]

droverdave posted a quite simple way to test it without bulb trickery , he did say one way , may not be by the FSM but it is a quite simple test so i validate his comment.