However, the automatic TPS also has a square four-wire connector, clearly embossed with the letters A,B,C, and D. It only uses three wires and provides information to the Transmission Control Module. THIS SQUARE FOUR WIRE CONNECTOR IS USED FOR TRANSMISSION/SHIFTING RELATED ISSUES ONLY.

First off, DO NOT UNPLUG THE CONNECTORS!

1. KEY ON, measure voltage between “A” positive and “D” ground by back-probing the connector. Note the voltage. This is your REFERENCE voltage.
2. Back-probe the connector at wires “B” and “D”. Measure the voltage. This is your OUTPUT voltage.
3. Your OUTPUT voltage needs to be eighty-three percent of your REFERENCE voltage. For example 4.8 volts X .83=3.98 volts.
4. Adjust the TPS until you have achieved this percentage. If you can’t, replace the TPS and start over.

So, if you have an automatic equipped XJ your TPS has two sides–one side feeds the ECU, and the other side feeds the TCU.

For those with a MANUAL TRANSMISSION–the TPS for the manual transmission XJs is stupid expensive. You can substitute the automatic transmission TPS which is reasonably priced. The square 4 wire connector is just not used.

Revised 7/08/17

 

Did you catch the part about the voltage decreasing as you open the throttle?

 

 

The confusion is that the extra square connector for the trans computer on the older Renix runs opposite of the flat connector that goes to the 4.0 engine computer. The trans computer in later years was changed to accept the same 0->5 volts signal that goes to the engine computer. The TPS sensor on the older renix also had slotted holes and was adjustable in the procedure Cruiser posted. The TPS on the later years was not adjustable.

I do not know if the 2.4l engine controller is the same, so it might have run backwards from the 4.0.

 

Thank you. I am doing my best to retain all of the knowledge everyone here gives me. I apologize, I simply ask if I don’t know.
thank you again.