1994 Isuzu Trooper Transmission not shifting automatically

Hello -

Also, one of my tech manuals wants to know if it is a LS, RS, S, or SE. I know you were not sure, but is there an emblem on the back or side?

I was able to find some info on the VIN for you. . ..I would keep this. It did answer my door question. . .. . ..

I am going to use the RS model for now.

Of course, you need a TECH 1 scan tool. . .. . ..can you break in. . .. . ..sorry. . .just kidding. . ...but, this does show you can jump pins 1 and 3 and get the Check Trans Light to flash also and count the codes. I attached the info for you. Now I know you did that for the check engine light, but this says for the trans light also. As a matter of fact, the pic I am giving you shows the Diagnostic Connector as a 2 pin and the TCM/ECM as a 3 pin. That way you can hook the TECH 1 scanner up to the 2 pin and still jump the TCM. If you can not, then you need to at least have the shop do this for you, give you the codes and tell you what they are also. But get the code numbers.

This would be great if you can get the codes though.

Right now, based off what you said that it is not shifting, the TCM contains a fail-safe system. When failure or problem exists in transmission electronic control system, the TCM may go into a back-up mode using pre-programmed values, allowing vehicle to be driven. The CHECK TRANS light on instrument panel will flash to inform the driver of a problem. The vehicle can be driven BUT shifting must be done manually. So, back to the codes. . .. . .. . .. . ..but at least you know why you have to manually shift.

Based on what you said about starting off in 3rd gear. . .it may be. The transmission has 3 different shift modes, Normal, Power, and Winter as I said. There is a TSB on the winter switch has failed. I have attached that for you.

Well, if you can not get the codes. . ..you cold take a chance and replace the winter switch and see if that fixes everything. Or, have the codes checked to make sure what is wrong.

Last, it looks like you may have some recalls on your vehicle. The dealer may fix these for free. Please contact the dealer service department, give them the VIN number of your car and have them check on these to see if they apply to you.

Hope this helps.

TECHNICAL BULLETIN # 248

DATE 1994

TRANSMISSION: 4L30E

SUBJECT: Third gear starts

APPLICATION: ISUZU 4L30E

Third gear starts

This condition can be caused by a winter switch (if equipped) that has failed, closed. When the winter mode is selected by the driver, the computer commands third gear starts for better driveability on snow or ice (the unit will still shift to fourth gear at the appropriate speed).

If the switch fails (closed) it can continually send a winter mode signal to the computer. For a quick test of the switch, turn the key off, disconnect the winter mode switch harness connector and drive the vehicle. If the transmission returns to normal operation replace the switch. The Isuzu part number for the switch is: 8-94368-568-1.

Recalls

Next please go to Auto Zone or O'Reilly's and for FREE they can pull the codes to the car. Most important: Once they check your codes, if they find something and you don't get it fixed and need to get back with us, please make sure you tell us exactly what the code was, number and all. Example, if the code was E0568 O2 Sensor bad. Then make sure you give us all of that. While there for FREE also they can bring their tester out and check your battery, alternator and starter.

Provide this info back and we will have a starting point.

No problem. But remember, I don't think you need the scanner. Try shorting 1 and 3 pin together on the 3 pin connector and see if the trans light flashes. Then that way you can just count the flashes and you won't need the scanner.

Have fun this weekend

Check the transmission range sensor.

Have a trans guy check this it is probably shot

That could be either a controller or solenoid problem. Your best bet would be to find a shop capable of puling the codes out of the trans to see what failures it may have recorded

Car will not shift gears into 3rd and 4th

Auto or stick?

Roy

All solenoids in that one. Have the PCM scanned to see if it stored a fault code related to the trans. Sounds like one is not working properly, should have stored something for us to start with

Could have hurt the computer when it was grounded out. Or with that electrical not working properly, it might have hurt the trans. Did you take it to a trans shop?

On something that old it might not. That is when it must be tested using a meter to check the solenoids, even that isnt 100%

Do you mean the shifter will not move?

Is this automatic or stick shift?

Roy