CRUISER'S MOSTLY RENIX TIPS

RENIX TPS ADJUSTMENT

OCTOBER 30, 2015 SALAD 205 COMMENTS

Before attempting to adjust your TPS, there are a few things that need to be done.

1. Be sure the throttle body has been recently cleaned. It’s especially important that the edges of the throttle butterfly are free of any carbon build-up.
2. With the KEY OFF, and using the positive (red) lead of your ohmmeter, set on the lowest scale, probe the B terminal of the flat 3 wire connector of the TPS. The letters are embossed on the connector itself.
3. Touch the black lead of your meter to the negative battery post. Wiggle the wiring harness where it parallels the valve cover and also over near the MAP sensor on the firewall.

If you see more than 1 ohm of resistance, or fluctuation in your ohms reading, some modifications to the sensor ground harness will be necessary. The harness repair must be performed before proceeding. It is covered in detail in Tip 6.

TPS ADJUSTMENT FOR ENGINE ISSUES

Both Renix manual and automatic transmission equipped XJs and MJs have a flat three-wire connector to the TPS which provides data input to the ECU. The three wires in the connector are clearly embossed with the letters A, B, and C. Wire “A” is positive. Wire “B” is ground. DO NOT UNPLUG THE CONNECTORS!

1. KEY ON, measure voltage from “A” positive to “B” ground by back-probing the connectors. Note the voltage reading–this is your REFERENCE voltage.
2. KEY ON, back-probe the connector at wires “B” and “C”. Measure the voltage. This is your OUTPUT voltage.
3. Your OUTPUT voltage needs to be seventeen percent of your REFERENCE voltage. For example: 4.82 volts X .17=.82 volts.
4. Loosen both T-20 Torx screws attaching the TPS to the throttle body and rotate the TPS until you have achieved your desired output voltage.
5. Tighten the screws carefully while watching to see that your output voltage remains where it is supposed to be. If you can’t achieve the correct output voltage, replace the TPS and start over.

Sometimes, after adjusting your TPS the way outlined above, you may experience a high idle upon starting. If that happens, shut the engine off and reconnect your probes to B and C. Start the engine and while watching your meter, turn the TPS clockwise until the idle drops to normal and then rotate it back counterclockwise to your desired output voltage.

TPS ADJUSTMENT FOR AUTOMATIC TRANSMISSION ISSUES

Renix automatic transmission-equipped XJs and MJs have a TPS with two connectors. There is a flat three-wire connector, same as the manual transmission vehicles have, and it is tested the same as outlined above—FOR ALL ENGINE MANAGEMENT RELATED ISSUES.

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.

 

done that too. i haven't tried to clean throttle body yet or make any tps adjustments. Heres my readings. Emc side 4.75 input .78 out put so .2 off going by calculations. Tcu side 4.59 input. 3.60 output by calculations off by .12. Is that off enough to cause my issues? I've still kinda been leaning towards shift solenoids in my opinion but I'm just learning transmission stuff. Thanks in advance

 

Those numbers are likely fine. Perhaps a TCU issue?

Solenoid issues can be checked at the connector in the engine bay.

 

solenoids are definitely where I would be going next, should be <14 Ohms from connector pin to earth

I think its solenoid 2, if it fails, you have no 2nd or 3rd, it kind of slides from 1st to 4th, surprisingly difficult to notice, feels a bit like slipping

There is almost certainly a Youtube that shows how to do it, connector in engine bay is easiest

 

which connector and what pins do I need to check resistance at? Again I greatly appreciate all the help

 

that is exactly how it seemed to be doing until I unplugged the tcu fuse

 

Roughly 11-17 Ohm IIRC on each pin to ground is what you're looking for.

 

ok so I got solenoids they are smaller but do fit and bolt up. Should i be concerned or put the pan on fill up and run it?

 

I'm guessing you've done the job by now but I'm pretty sure the replacements aren't an exact match shape/size wise, and as long as they bolt up correctly, they're good to go.

 

yes installed them and all seems to be working fine now

 

Great to hear