Thread: Help needed please for the installation of a vdo temperature gauge

Hi mate!
No fun, all these cables i guess . Well, if I understand the diagrams correctly, you will have to connect the green-blue cable, coming from the sensor, to Pin 5 of the new gauge. Pin 1 is connected to 12V coming from the ignition barrel or through a relay, activated with the ignition. Likewise Pin 8. Pin 2, 3 & 7 go to ground.
It appears, though, that "signal ground" (Pin 3 that is) should go to a different ground connection than the other two. Don't ask me why, I'm not an auto electrician (not an ordinary electrician either, btw). That's the way I'd connect it up and see how (if) it works. Trial and error, basically .
Good luck!
Cheers

Happy to see this thread as I have similar plans. I think in addition to the VDO viewline gauge, you also need to replace (or somehow add) a new VDO sender. The VDO senders can be purchased with different alarm triggers which if the coolant temp reaches that temp (for instance you can buy a sender with an alarm signal at 95°C, or 100°C, 105°C, 110°C) will set of the red triangle LED light in the VDO gauge.
I would love to add this, but would prefer to leave the standard water temp gauge functioning, and add somehow additionally the VDO gauge with its dedicated sender.
I actually have started yesterday a thread about this on defender2.net, which might be interested to follow.
Like you, I am not happy with the fact that the standard water temp gauge needle in the truck sits solid in the middle position until the coolant temp gets hotter than 115°C, and then flips straight to red with limp mode and often serious engine damage as result.... Better to know the exact coolant temp all the time so that you can adjust your driving style timely.
Here is the defender2.net thread link about this.
Eric
DEFENDER2.NET - View topic - Puma water temp gauge function

Hi Ericvv,

I have installed and wired the gauge, as you say in your thread on defender2.net you need to install a VDO temperature sender with the VDO gauge in order to have a proper reading of the temperature.

For the wiring, a multimeter is needed to find out the relation between the VDO socket and the pins. (not mentioned on the electronic installation guide!)

I found some more installation information on another site (french) that helped me understand that some wires are not to be used and that another sender is needed for the alarm light. Mind that I also learned from your post that VDO produces senders that cover both functions.

here is how I wired the gauge:

pin1: Positive 12V (ignition) wired to the Green cable (G) on the existing wiring loom.
Pin2: Negative ground
Pin3 and Pin 4: not assigned
Pin5: Sender signal wired to the Green and Blue cable (GU) on the existing wiring loom.
Pin6: Positive lighting wired to the positive wire of the binnacle illumination.

I didn't use the following pins because I don't have the proper sender to trigger the overheat alarm signal.

Pin7: Negative ground for the overheat alarm signal.
pin8: Positive overheat sender alarm signal. (needs to be added to the added to the loom)

I have noticed few things after the installation, the illumination of the new gauge is red and doesn't match the green illumination of the other original LR gauges and dials, maybe it is a positive thing to draw the attention of the driver to this important gauge, yet I don't like the BMW look.

I still have to figure out why the new gauge doesn't illuminate with the others unless the ignition is turned on.

I didn't test the new gauge yet as I am installing a new radiator and cleaning the heater matrix. I will update the thread once everything is finalized.

I have changed the radiator that was still genuine, the 110 is a 1989 model, though it has been well looked after with a bi-annual rodding and coolant replacement, their was a significant leak at the bottom, the decision was made to replace it with a new copper 4 core high exchange matrix.

At this stage I decided to check the entire system, so the heater matrix was next to be checked.
I have been facing poor heating in winter so was expecting to find a clogged matrix, yet what I found was a corroded and leaking unit. By the way couldn't they design the heater box in a way to give access to the heating matrix without dismantling the entire box?
I searched for a new matrix but couldn't find any, all 110 of this age came without air conditioning thus what was available was a different type that has a different mounting. Back to the radiator shop where a new and expensive unit was tailored made.

The new cooling system has been put to the test with the first heat wave of the summer. The ambient temperature was 35C and was driving uphill ( from sea level to 1400m)
The VDO gauge was moving between 80 and 93 C, so I guess that it is a good performance from the radiator, by the way I have a 4.2 engine fitted to the 110.

Originally Posted by lebanon

SORRY, SLIGHT THREAD HI-JACK -
I have noticed few things after the installation, the illumination of the new gauge is red and doesn't match the green illumination of the other original LR gauges and dials, maybe it is a positive thing to draw the attention of the driver to this important gauge, yet I don't like the BMW look.

I've bought VDO before and they came with a white bulb, together with a red and a green "sock" to fit over the bulb if the buyer wanted one of those 2 colours. Could it be that your builb has a red "sock"?