Canadian Hummer Club Forums

Hello to everyone! My name is Pavel and I own a 1995 H1 Wagon with a 6.5 NA. When I got it the speedometer did not work and I have read about them failing around the 90k mark which I am at now. I read on Flashoffroad about replacing it with a VDO and went ahead and bought one. When i was installing it i noticed that there has been a modification with the harness. The yellow wire which I believe is the signal to the speedo has been bypassed with a black wire. I traced that black wire and it goes directly to the vehicles speed sensor. I had the idea that the signal is sent to the digital ratio adapter and then to the gage. I want to make this right and am looking for some knowledge. If i hook up the speedo with the black wire i can get it to read the speed but the needle does not stay steady. It tends to show plus or minus 2mph. If anyone has a wiring diagram showing how the speedometer is wired to the speed sensor please share. Any other information would be greatly appreciated. Thank you.

What is a VDO and what is it four.

[quote name='logicbyondreason' timestamp='1317586064' post='30907']

Hello to everyone! My name is Pavel and I own a 1995 H1 Wagon with a 6.5 NA. When I got it the speedometer did not work and I have read about them failing around the 90k mark which I am at now. I read on Flashoffroad about replacing it with a VDO and went ahead and bought one. When i was installing it i noticed that there has been a modification with the harness. The yellow wire which I believe is the signal to the speedo has been bypassed with a black wire. I traced that black wire and it goes directly to the vehicles speed sensor. I had the idea that the signal is sent to the digital ratio adapter and then to the gage. I want to make this right and am looking for some knowledge. If i hook up the speedo with the black wire i can get it to read the speed but the needle does not stay steady. It tends to show plus or minus 2mph. If anyone has a wiring diagram showing how the speedometer is wired to the speed sensor please share. Any other information would be greatly appreciated. Thank you.

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Here you go. Hope it helps!

ARE YOU TALKING ABOUT THE DRAC BOX

I RAN INTO THIS ISSUE RUNNING BIGGER TIRES

DAKOTA DIGITAL ALSO MAKES AM EASY MODULE THAT HOOKS DIRECT TO TRANNY SPEED SENSOR THAN TO SPEEDO THAT IS ADJUSTABLE

I would have though the ECM would have filtered the signal but then i realize its a 95. After seeing the diagram it looks like the dra is the middleman. Learn something new everyday.

Pins 7 and 12 on the dra are input from the sensor that tames the resolution and output the hi res signal on pin 10 to the cluster.