Yellow box speedometer calibrator wiring help

ShawnR

VCA Member
Joined
Jun 1, 2021
Posts
20
Reaction score
2
Location
Central, OH, USA
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

Enthusiast
Joined
Aug 18, 2018
Posts
4
Reaction score
0
Location
Bethesda, MD
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

Enthusiast
Joined
Feb 16, 2023
Posts
14
Reaction score
2
Location
Franklin County, PA
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.

You must be registered for see images attach
 
Last edited:
OP
OP
ShawnR

ShawnR

VCA Member
Joined
Jun 1, 2021
Posts
20
Reaction score
2
Location
Central, OH, USA
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

Enthusiast
Joined
Sep 8, 2021
Posts
5
Reaction score
0
Location
92084
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.
 

Goggles Pizano

Enthusiast
Joined
Nov 25, 2009
Posts
510
Reaction score
116
Pin 3 of the 3 pin vehicle speed sensor connector.

Easy to find. Pin 1 = 5V, pin 2 = ground.
 

Forum statistics

Threads
153,609
Posts
1,684,960
Members
18,179
Latest member
Luigi93
Top