Replacing old VDO Temp Gauge with NEW VDO temp gauge...wiring question

tuna_fan

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Need some input here. I'm replacing old VDO with new one...they dont make the old one anymore.
Engine is 2001 CAT3126...dont know anything about the sending unit.
Here is a pic of the OLD gauge, with sketch of how its hooked up.
Under it is a diagram and explanation of the NEW gauge.

Some of these are easy:


Old Purple (+) goes to new Red (+)

Old Orange (s) goes to new Green (sender signal)

Old Yellow (ground) goes to new Black (ground), and maybe new Blue/Black (signal ground)

Old Blue (R) goes to new …. Not sure either Warning (+12) or Warning (-)

Jump old Purple (+) to new Blue/Red (12v+ Illumination)


I think old purple (+) is getting power from the ignition switch…

Water-Temp-Gauge-diagram.jpg
 

captjohn

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On the old gauge:
The blue wire supplies power to the light bulb to illuminate the gauge.
The yellow is the ground to the bulb.
The purple wire supplies power to the temperature sensor.
The orange wire is the return from the temperature sensor.
And the yellow wire is the ground connection to the temperature sensor.

On the new gauge:
The blue wire goes to pin 6, (Illumination 12V+).
The orange wire goes to pin 5 (Sender Signal).
The purple wire goes to pin 1, (Battery 12V+)
The yellow wire goes to pin 2 (Ground)
Pins 8 and 7 look like they supply power and ground to an over temperature warning light that you probably don't have.
Pin 3 is used if your temperature sensor is a two terminal temperature sensor, for ground. Your not going to use it.
And pin 4 is unused.

If you jumper pins 1 and 6 the illumination light will be on whenever the engine is running, you don't want that. The blue wire is probably hooked up to your running lights switch. When you turn them on, the gauge lights come on.

I hope this is helpful!!!!!
 

ArchHibb

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tuna_fan - I need to replace the same VDO gauge for my 3116. Thought about going all digital, but no gauge manufacturer makes all the gauges I’d like to switch/ incorporate; at least 1 will be missing like trans pressure or (surprisingly) water temp. What style VDO replacement did you choose?
 

tuna_fan

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On the old gauge:
The blue wire supplies power to the light bulb to illuminate the gauge.
The yellow is the ground to the bulb.
The purple wire supplies power to the temperature sensor.
The orange wire is the return from the temperature sensor.
And the yellow wire is the ground connection to the temperature sensor.

On the new gauge:
The blue wire goes to pin 6, (Illumination 12V+).
The orange wire goes to pin 5 (Sender Signal).
The purple wire goes to pin 1, (Battery 12V+)
The yellow wire goes to pin 2 (Ground)
Pins 8 and 7 look like they supply power and ground to an over temperature warning light that you probably don't have.
Pin 3 is used if your temperature sensor is a two terminal temperature sensor, for ground. Your not going to use it.
And pin 4 is unused.

If you jumper pins 1 and 6 the illumination light will be on whenever the engine is running, you don't want that. The blue wire is probably hooked up to your running lights switch. When you turn them on, the gauge lights come on.

I hope this is helpful!!!!!
Wow !! Thank you so much for this!! I will give this a shot and report back.
I DO have a seperate warning light panel that i assume has a wire connected from the sender directly...I think....
Thank you for taking the time to write all of that for me!!

Arch - I bought a "ViewLine" gauge, #A2C53413386-S" from Amazon:

https://www.amazon.com/VDO-A2C53413386-S-Temperature-Gauge/dp/B00T9LJJQM
 
Last edited:

Harloo

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Good morning tuna_fan,
Do you happen to still have the old gauge? I need the white plastic body of that gauge because the mounting tabs on mine have crumbled but my gauge still works fine. The electrical tabs on mine are identical to yours.
thank you, Denny

267BA44F-0779-455F-BCE1-07D623FEED53.jpeg
 
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