29 replies to this topic

[hanra]

What sort of instrument cluster do you have?

[S pack]

It is normal for thermal instruments to fluctuate a little above and below the average reading.

The fuel gauge in our VS used to fluctuate up to 1/8 of a tank above and below the average reading.

Edited by S pack, 13 January 2017 - 01:41 PM.

[hanra]

Ok so none of the other 2 gauges fluctuate? Oil pressure and temp?

[VDO]

Taking the gauge all the way to full scale on start up, if there should be a lower reading, indicates a voltage regulator that's "priming" (holding 12 volts to pre-heat the bi-metal) for too long.... BAD.

 

The pointer wavering when settled, indicates a voltage regulator that is taking a long time to re-heat on each pulse... BAD.

 

These are both signs of the voltage regulator dying, due to burnt windings on it's bi-metallic strip... BAD.

 

Replace it NOW, because when it does die, which is going to be very soon by the sound of things, it will die in the "closed" position and completely fry all three gauges.

Edited by VDO, 14 January 2017 - 08:52 AM.

[hanra]

Does your temp and oil gauge play up?

[hanra]

Wack one of these in if you cant source a bi-metallic strip style regulator.

 

https://www.jaycar.c...ulator/p/XC4514

 

Or fit a VDO fuel gauge.

[Uncle Chop Chop]

Use a multimeter on the output of the GMH "voltage regulator", it's supposed to be 5V. As was said in post #7, when it dies it allows the full 12V through to the guage. I had that happen to me in my HJ many years ago.

[VDO]

Use a multimeter on the output of the GMH "voltage regulator", it's supposed to be 5V. As was said in post #7, when it dies it allows the full 12V through to the guage. I had that happen to me in my HJ many years ago.

Can't test bi-metal voltage reg with a multimeter.

It will only show the pulsing of the 12v.

The Jaycar option is the best.

[Uncle Chop Chop]

I never tried it, but I thought it might work.

[EunUCh]

Dunno much about them ! , does anyone have a car that either has the pinger still working or the pinger replaced by a solid state

reg. that can tell us if the other needles come up slow or is it just the fuel needle that takes its time ?

 

Personally i would go the 3 pin reg. with a small heat sink , it's simple , it's small and it funnily enough it works and only has 3 wires.

 

Although not 100% familiar with how they worked on the LH/X ,checking out a UC set up they may have  lifted the ground of the solid state reg. to give a slightly higher output but that is yet to be confirmed.(on UC).

It's not impossible to measure the output of a pinger reg. but you will need an archaic analogue meter to get a reasonable idea .

 

 

[VDO]

All the pointers running off the voltage regulator should move at roughly the same speed.  Only the Volt gauge will move a bit slower as it's on a separate circuit.

 

I've installed probably 50 of the Jaycar Arduino type regulator and found them to be very stable and reliable.  No heat generated, as it's a digital switching power supply.

 

Alternatively, those little TO220 style 3 pin regulators generate a considerable amount of heat.  The hotter it gets, the less stable it is and they are somewhat unstable at the best of times, which results in inaccuracy.  Also one less thing in the dash that generates heat is probably a good thing for safety.  You could supplement it with some caps and resistors to smooth it out, along with a decent heat sink, but then why not get the Jaycar one which is more refined and it's virtually ready to go and generates zero heat.

 

As for measuring the voltage output of a bi-metal "pinger" regulator, sorry guys, but no analog or digital voltmeter will measure it, no matter how old.  It can only be measured with a BI-METAL volt gauge which reads from zero to something over 5 volts, and I'm sorry to say, no one makes them.  I went through this dilemma years ago and eventually bit the bullet and invested in some hard to find old Smiths test equipment from the UK, made specifically for this purpose.

 

If you need help hooking the new reg up, just ask, no worries.

Edited by VDO, 18 January 2017 - 07:23 PM.

[EunUCh]

Funny that , been playing around with an old scope , and the only meter that would give a half decent reading on what the sweep generator was doing was an old vane thing , mind though the time base was on a low sweep time which helped a bit disregarding vane dampening factors .A cro is nicer.

 

Got about 6V on the old analog vane shit , give or take some technical jargon , similar shit , on/off given some some sort of pre calculated engineers advice.

 

So, do we know if  some other needles are run off this 5V reg supply  "pinger" or are we just guessing?

 

Is there a cct diagram somewhere that shows us  what this pinger actually supplies power to ?

[fuzzypumper]

The regs are marked 50/5/1.  I read that to be 50% duty cycle, 5v , 1 hz frequency.

Correct me if i wrong Mr VDO.

 

Although having tested a few of these i found it was more like 2-2.5hz frequency.

 

The arduino dc to dc stepdown is the best choice as a replacement.

[VDO]

The on/off frequency of the "pinger" regs varies quite a bit, depending on the load, but eventually they will settle to maintain a "steady" output, once the gauges have settled and reached their respective levels.

 

Without any load, I've found that they average just under 1 Hz, in good condition.  The frequency can be adjusted, but will still slow considerably under initial load.

 

Generally the fuel temp and oil pressure gauges will be fed from the "pinger" reg, if they're the bi-metal type, but this is not always the case.  In some instances, Ford have mixed the cluster with some bi-metal and some magnetic gauges.  The reason generally being that the fuel and temp gauges required some damping and the simplest way to achieve that was to use bi-metal gauges, due to their slow reaction time.

 

In another twist, early Commodore clusters (VB VC VH VK VL) use magnetic gauges for the top two gauges (volts and oil pressure) but use bi-metal gauges for the bottom two (temp and fuel), BUT the bi-metal gauges here run on 10 volts.  These clusters use the little 3 pin reg for the bottom gauges, with very little heat sinking and as a result have a very high failure rate.

Edited by VDO, 19 January 2017 - 07:07 AM.

[Statler]

Chris, would you consider making a thread on replacing the regulator with a more modern unit?

 

People just don't want to post away their gauge clusters these days due to the risk of loss/damage. 

 

A 'How to' would be beneficial to the Site.

[hanra]

I imagine it would be along the lines of this.

 

Would pay to have a decent soldering iron and a Digital Multimeter.

 

I found it best to run a dedicated GND to my poxy little heat sinked LM7805, to avoid inaccurate readings when the lights were turned on. Id probably be inclined to do the same here.

Attached Files

•  Untitled.jpg   64.35K   6 downloads

Edited by hanra, 19 January 2017 - 10:18 AM.

[VDO]

This unit doesn't require a dedicated ground.  It's very very stable.

 

When I install one, I always test the stability of the output.  Using a digital volt gauge, I set the output at between 5.0 volts and 5.1 volts with feed in voltage at 13.8 volts.  It's better to be slightly over 5.0 volts... 5.05 volts is ideal.

 

To check the stability, I then reduce the voltage input to 7.0 volts, and then increase the input voltage to 20.0 volts.

 

Always, the variance is only + or - 0.01 volts across the entire range of 7.0 to 20.0 volts.  That's good enough for me.

[Statler]

Or maybe even add the info to this thread.

 

http://www.gmh-toran...r-dash-cluster/

[Cook]

Hi all. I had posted before about my issues with the fuel gauge but can't find the thread for some reason so will continue here.  On a suggestion from Chris "VDO" I bought a fuel sender resistance interface and about to fit it up but one thing puzzles me. No where in the instructions does it say you have to fill/empty etc, the tank while you calibrate it. So am I correct in thinking it will magically do it regardless of the amount of fuel in the tank or have they missed a step in the instructions. Thanks in advance. Cheers Ron

Attached Files

•  Fuel Sender Converter.jpg   94.47K   2 downloads
•  Fuel Sender Resistance Insrtructions.jpg   37.1K   5 downloads

[S pack]

Reading the instructions it sounds like you need the sender unit removed from the tank so you can operate it from full to empty by hand to calibrate the interface module.