warning lights

Good Morning.

can someone offer some knowledge and expertise

I have GTI 1.8 cab the temperature lights come on and squeals almost immediately after starting. The temperature gauge shots up into the red after a a few minutes.

The sender and sensor have been checked. I have another set of clocks but they seem no better than the ones I have.

would changing the whole clock system, using the new as a donor for parts (if possible) or can I fix the fault

Any advice would be much appreciated.

Looking forward to any ideas

 

First I would ask to differentiate the flashy light and the
Squeal.

why because on later Cabriolets and some golfs the light means a couple of things, the Squeal is only one thing that means something else.

The squeal is it more like a buzz? as the only thing that "squeals" is the Low pressure at High RPM, it is located in the rear of the speedometer housing itself, and it will light the light in the temp gauge. This is controlled by the White Sending unit on the Oil filter flange. If the wire is off and shorting to ground that will cause the buzzer to buzz. So test it, the Sender, shorts if their lower than 1.5 bar on the oil pressure when the RPMs are over 2000 RPM. So if you remove the wire off the sender and don't short it to ground there shouldn't be any Buzzer.

The Temp gauge is prone to a couple of different things.
a bad sender that shows short when tested will ground the gauge, and cause the Light in the middle to flash after it gets 3/4 to full deflection. Depending on the years it is either a single pin black sender on the water outlet flange, or a Dual Pinned black Sender on the plastic flange on 90-93 Cabriolets.

Using a Test light or DVOM you can Validate that the sender is good or bad, bad is a direct short to ground and your DVO either shows 0 ohms, or rings the buzzer.

If you turn on your car to run, engine not running, as in first on (not started) and your water gauge climbs to full hot or off the mark towards mid scale, then you usually have a issue with the sender, or wire to the gauge.

If you take your wire off the sender, and Using a 9VDC battery, Plus on the colored wire and ground on the engine frame or the brown wire (90-93 Cabriolets) it should move the gauge from cold to 3/4 deflection.

If your fuel gauge and the water gauge both are acting funny, then your 10v stabilizer is bad.

The other thing that I have seen is cold solder joints on the water and fuel gauge that causes intermittent fluctuations of the Gauges or they stop working.

In the archive sections (click the link in my signature) there are how-to's to fix the gauges.  

I tend to thing you have a bad sender, and or a shorted wire They are separate systems that one have the cluster in common.

WOW!!!  Brian1234 that is very thorougher answer. Thank you very much.   
Yes it is a buzz.
The fuel gauge works well.
the water gauge does go to red on just turning the ignition on.
I am going to start with the sender first hopefully will get  time this weekend.

Thanks

Have a great weekend.

Sorry I was a bit rushed to make a DR. appointment and I forgot the blinky light on latter Cabriolets could mean that the a/f is low. So I added a few pictures.

On my 90's Cabriolets there is a coolant level sender on the expansion tank.  This sender can get corroded and cause the light to blink for low coolant, and if when your coolant is low when cold, it can blink.

So if you have a Coolant level sender, you may want to take it out when the engine is cool, and clean the little probe tips.

Just be sure that your o-ring is lubed with with either silicone grease or Vaseline.

IIRC it is either a 27 or 28 mm socket that takes the thing off just don't over tighten it.



Oil pressure controller is behind the faceplate of the speedometer





Low pressure High RPM sender.

Hi
Thanks again. Been off line building a  New house for my  golf. Its just finished. I'm getting back on it. Still have the issue, going to look at it again.

Thanks  

Hello all,

I have a 1988 Caddy 1.6D (JK engine). The coolant temp gauge is always on full cold and does not seem to work. Fuel gauge works and temp red light blinks and stops when I turn on the ignition, as it should.

Coolant temp sender shows reasonable resistance when measured with multimeter.

I took off the instrument cluster and connected the temp gauge to 9V battery as I read from another troubleshooting thread. The needle deflected to hot as it should.

Briano1234 said

If you take your wire off the sender, and Using a 9VDC battery, Plus on the colored wire and ground on the engine frame or the brown wire (90-93 Cabriolets) it should move the gauge from cold to 3/4 deflection.

I did this to the temp sender wire, but nothing happened on the temp gauge.
When measuring voltage from temp sender wires (Y/R and BR), there is no voltage when ignition is switched on. I guess there should be?

I hope I understood correct, english is not my language and electricity is even more stranger to me…

I would be very grateful on any input!