Yellow box speedometer calibrator wiring help

ShawnR

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I'm in the process of doing the 3:55 gear swap (2001 GTS) and the kit came with the "Yellow box" speedometer calibration unit. It says to interrupt the speedometer signal wire..... Anybody know exactly where that is (and colors would be nice too).

The box itself doesn't really look weatherproof so I am also wondering where anybody else installed their unit. Under hood, under the dash, down by the transmission..?

Thanks in advance.
 

Shakazito

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When I bought my 2001 RT/10, the Yellow Box was inside the cover of the PCM. I found the box to be unreliable and had Dan Cragin recalibrate my speedometer through the PCM.
 

Gibz

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I am about to install a yellow box on my 2001 GTS. There are instructions online, link below. I plan on doing a youtube how-to video when I do it but might be a little bit till I get around to it. there is a speed sensor near the output shaft of your transmission, it should have 3 wires coming out of it to a white connector. Picture below. I plan on intercepting the signal between the sensor and that connector, so if something goes wrong worst case is I can just replace that sensor and I have not touched the engine or chassis wiring harness. I have not found where I will put the little box yet but it should not be too hard to tuck it somewhere relatively safe.


I have found that the company is responsive and good with details: [email protected] , but not familiar with our GTS systems and the potential impacts to the ABS module. From what I have found is modifying the sensor signal where I mentioned earlier should not impact ABS but I have not confirmed it yet.

If you figure it out let me know, if / when I figure it out I will follow-up with instructions.

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ShawnR

ShawnR

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I'm probably not doing it until spring, but please keep the thread updated as to what you learn. I like the idea of tapping into the signal at the trans sensor instead of the PCM. It just seems like it is less likely to screw something up.
 

2001rt10

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Hi folks...is there an update on this? I've also upgraded my '01 RT/10 to 3.55 and would like my speedo/odo to read correctly.
 
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