LINK AS-UPPER 2898390 - Caterpillar

The Procedure for Outside the Engine Mounted Instrument Panel
There are four speed sensor mounting holes already machined in the top of the engine's rear housing. The machined mounting holes are all located in the centerline of the flywheel ring gear. If one of the machined mounting is not empty, then remove the 6V-2455 Speed Sensor Gp . The 6V-2455 Speed Sensor Gp has a shielded connection for the cable harness, and the sensor is labelled "ESS". However, if one of the machined mounting holes is empty, install the 237-5337 Speed Sensor in the empty mounting hole.
Screw the 237-5337 Speed Sensor in all the way. Loosen the 237-5337 Speed Sensor 3/4 of a turn. This will properly set the air gap.
Review the next step before performing any procedure in order to properly determine the appropriate length of the 143-2455 Electrical Cable that is going to be needed during the next step.
Take an appropriate length of 143-2455 Electrical Cable and run the 143-2455 Electrical Cable from the 237-5337 Speed Sensor to the "connector C". This will give an estimated amount of the 143-2455 Electrical Cable that is going to be needed. Follow the instruction below in order to properly connect the 143-2455 Electrical Cable to the 237-5337 Speed Sensor .
Connect the dark gray wire from the 143-2455 Electrical Cable to pin one on the 237-5337 Speed Sensor connector.
Connect the green wire from the 143-2455 Electrical Cable to pin two on the 237-5337 Speed Sensor connector.
Connect the white wire from the 143-2455 Electrical Cable to pin three on the 237-5337 Speed Sensor connector.If necessary, use shrink tubing on the wire connections.
Attach the 143-2455 Electrical Cable to the engine's main harness. Run the 143-2455 Electrical Cable to the 40 pin connector "connector C". The "connector C" is located on the bottom of the engine's instrument panel. Follow the steps below in order to properly connect the 143-2455 Electrical Cable to the "connector C".
Connect the dark gray wire from the 143-2455 Electrical Cable to pin one on the "connector C".
Connect the green wire from the 143-2455 Electrical Cable to pin two on the "connector C".
Connect the white wire from the 143-2455 Electrical Cable to pin three on the "connector C".Reference for Troubleshooting
Illustration 3 g01380357
Old Diagram before converting to the 234-8717 Switch
Illustration 4 g01380358
New Diagram after converting to the 234-8717 Switch