I'm no expert in electronics but I don't think here is a stabiliser in the system beyond that in the alternator, unless there is some sort of one built into the gauges themselves. Series vehicles had a regulated 10v (I think?) supply behind the instrument panel which fed the gauges.

I think the gauges on a 90/119 don't mind if it's 12v or 14v, as the reading comes from the difference in resistances between the gauge body earth and the earth path through the sender. That's why a bad earth on the engine block can cause dodgy readings, as it affects that path. A reading of let's say 90 degrees might be 6v on the system with a 12v supply but it would be 7v on a system with a supply of 14v, as the gauge is just comparing the two.
 
Might have found the reason for the erratic temp gayge, missing my engine earth, what should it run from starter?

 
New engine- chassis earth put on as it was missing!
No more gauge moving when lights/ anything turned off/on.

But the gauge does read cold, at normal operating temp it sits at 1/4 on the gauge when it should be sat on half obviously.

Any way around this or not?
I've tryed the genuine Land Rover sender that was £23 odd and a cheap £3 all makes4x4 one and the cheap one reads slightly better but not a lot...
 
Bit of a long shot but with engine warm can you run a good earth to the outer casing of the sender
Keep it clear of the centre or near the green insulation
See if this livens up the gauge to somewhere civilised
I've heard of issues with non genuine senders but usually just failures rather than outright not working
Also is engine well earthed, I'm sure it is seen as it starts


Earths are good
Presume all the earth pins are good for gauges, there's 2 black and one black grey?
Worth making sure any crimped terminals are good with no excess insulation etc
Namely on the temp gauge wire rework just in case there's resistance issues
 
Earths are good
Presume all the earth pins are good for gauges, there's 2 black and one black grey?
Worth making sure any crimped terminals are good with no excess insulation etc
Namely on the temp gauge wire rework just in case there's resistance issues

All checked and checked again from start to finish. Just need it to read a 1/4 more.

Retro or anyone; do you know if different senders will give a higher reading?
I tryed the black 300tdi defender sender and that doesn't work at all,
Any other senders with similar ohms to show a different reading??
Max
 
I wonder if the positive ign feed is part of the issue
Can you remove the white/green ign on wire power supply from temp gauge and run a new wire from battery positive temporarily to the temp gauge
Then try the accuracy of the gauge once engine is warmed up
Also try lights and heater to see if any changes occur
I'm suspecting power being robbed by the lighting circuit or heater dropping a few volts
 
I wonder if the positive ign feed is part of the issue
Can you remove the white/green ign on wire power supply from temp gauge and run a new wire from battery positive temporarily to the temp gauge
Then try the accuracy of the gauge once engine is warmed up
Also try lights and heater to see if any changes occur
I'm suspecting power being robbed by the lighting circuit or heater dropping a few volts

I'll try that, sounds like somwhere to start anyway hahaa
 
The green sender should read correct for you but at this rate my td5 gauges are getting fitted this weekend so hopefully I'll be able to compare my readings
 
The white/ green wire in the td5 dash harness comes in via plug and runs to a spliced joint separating to individual wire feeds for speedo, fuel and temp supplies
I'd look closely at it as spliced joints are notoriously ****
Running the battery feed will help eliminate it
 
Yep like ya say it could not be getting enough juice, will test it in daylight and see how it behaves. Cheers for now.
 
Whatever voltage (12v +) doesnt really effect the reading.
It just reads 1/4 cold all the time.
Rather annoying lol.
 
Interesting reading, something I want to do soon unless I can find someone who willing to do it for me! I hate electrics!
 
I did this 8 months a year ago and it really is much better. The TD5 gauges are far easier to read and the fuel gauge is far more accurate and doesn't keep going up and down. I managed to find a bargain on ebay and got the TD5 speedo, temp gauge, clock and fuel gauge plus the binnacle for £55. Just make sure you use the genuine transducer apparently the others are rubbish.
 
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I got a cheap one think it's allmakes4x4 brand and seems ok! Speedo is Abit out as I'm running big tyres so not to worry lol.
Cowaski you temp gauge work out ok???
What brand sender you using?
 

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