VN Temperature gauge not working

[IvegotaCommy]

The temperature gauge on my VN is not working. Other posts I have read indicate that the temp sender is needed to set the fuel to the engine so I can not just ignore. Not in my nature either, some people can ignore something not working right - others can not.
Engine starts OK and the fuel economy seems OK. Does this mean it is just the gauge? Is it fed from a fuse? If it is a fuse, what else is on the same fuse that I can check to see if they are not going? Maybe a connector to watch out for? Cheers

[Morton]

It would be one of three things:

1) your water temp sender is faulty
2) your water temp sender is unplugged
3) your dash gauge is faulty

First two are the easiest to check:

Remove the left hand bolt of your anternator, and swing it up. Behind it, on your inlet manifold, are two sensors bolted in. The one on the right has two wires and is your sensor for the ECU, and the one on the left has one wire, and is your sensor for the dash gauge.

If you want, you can replace the sensor on the left (the dash gauge sensor) for around $12. It's easy to unscrew, and you won't lose much water at all while doing the switchover. (obviously check if the sensor is plugged in first. The wire sort of slides over the top of it.)

If this doesn't rectify your problem, then it's probably easier to try sticking on a second hand dash cluster. If that fixes it, then it's a cluster issue

Don't worry about your fuel issue. Your ECU and your dash gauge run from different sensors, so if your dash reads nothing, the ECU probably still knows what temperature things are running at. Although if you're going to change the smaller sensor, it's probably worth changing the ECU sensor too while you're behind the alternator. Only around $15 anyway

Hope this helps.

[IvegotaCommy]

Thanks, Morton. I was under the impression that the sensor was common. Much easier now that I know where the sensors are. I will check it out some time but now I know the temp gauge not working does not effect the engine I can wait until I get other things done.

[m0zzaVP]

also try this.. give the dash above it abit of a bash. works if its a sticky gauge.

[IvegotaCommy]

Well, further down the track, now. Thought I would post an update. No, it was not sticky gauges. Took them out and checked thoroughly.

It was not the sender unit. Replaced it with a new one. Thanks to Morton who said the sender was under the alternator. The advice was spot on. The book I read said it was at the rear of the motor on the drivers side but evidently it was changed for the 91 VN.

Shorted the sender to ground with the ign on and the gauge goes right up to max. Measured the resistance of the sender and seems OK. So what is going on? Could it be possible the coolant (in the intake manifold) never gets hot? Maybe a blockage in the water passages? The gauge still does not read anything.

[Morton]

Nah, I don't think a blockage would cause the temperature to stay down. Even if the water wasn't flowing, it would still heat up.

Perhaps it's time for you to fit an aftermarket temp gauge? I was getting strange readings from mine, so I installed a whole new Specometer gauge just next to my dash. Works a wonder, and now I always know exactly what temp my car is running at

I then hooked my dash gauge up to a second sender I installed outside the thermostat on the return hose. It's just basically there to make the needle still move, 'cause it would bug me if it was dead ^^


How long do you drive your car for? Just short trips? It's possible that it will take a while for the gauge to show anything... You've got me puzzled really?! lol

[IvegotaCommy]

Someone had taken the thermostat out. Temperature gauge was OK. Just temperature never read. Put in a new thermostat and reading normal.