98 Neutral Safety Switch

I just bought a 98. The previous owner says he just had the NSS replaced. He drove it for a couple of weeks and everything worked well. When I came to pick up the vehicle it would only shift 1-2-3 but will not hit OD(4th). It feels like the Torque Converter locks.

The check engine light came on. I took it to a local mechanic and he reset the codes. Felt like it was hitting 4th again. Then after 4-5 miles the light came on again and now it will not hit 4th again.

I had trouble with my 2001 shifting in and out of 4th and it was the TV cable and I adjusted it and that problem was fixed. Its not the cable on this one.

Do you think that the mechanic changing the NSS just shorted a wire or just did not connect it all up correctly. How hard would it be for me to go throught that myself?
I saw the right up on the AW-4 and which solenoids should activate in which gear. I just don't know how to go through that. If you have to take the pan off to check then how would you simulate driving. Are there contacts under the dash that you could check?

Start with the obvious, download and post the exact 4 digit Check Engine Light trouble codes. You Jeep is trying to tell you what is wrong.

It is pretty easy to find the AW-4 Service and Diagnostics Manual on the Google. You can follow the trouble shooting check lists and perform the specified tests to determine the nay AW-4 faults.

Thanks for the help.
It's P0700 Trans Ctrl System Malfunction
P0705 Trans Range Sens Malf (PRNDL)

I'll look for the manual you reference.

The NSS most likey still nees to be adjusted. I could say there are threads and make you look for them but...

With the ignition on, engine not runningm place the transmission into reverse. Rotate the NSS until the back up lights are off and then slowly counter rotate until they just do. Note the position of the switch. Continue the counter-routation until the lights go off and then rotate the switch until they just co again. Note the position of the switch.

Place the switch into the middle of the two noted positions. This is your starting point. If the P0700/P0705 codes continue to appear, make extremely minor adjustments to the switch. Does not matter which way you go first as it will, most likely, be the wrong way. Murphy, you know... If it continues to throw the codes, move the switch back to the mid point and go the other way. It took me two minor adjustments to get the thing where it was happy. I am talking less than 5 degrees of total adjustments. The contact width in the switch is very small.

Hope this helps. If the TCM does not know exactly where the linkage is, it throws those codes.

Awesome,

Did as you said and the issue is fixed. No codes and I've got 4th gear again. Thanks a lot!

It is why we are here...

The reason for overshooting the points and coming back is to find the edge of the moving contact with relation to the fixed. This method provides the best chance at fing the center of the fixed contact. Do not be purprised if it has to be tweaked in a couple of months. Took a couple of shots for me, but it has now been stable for over a year.