AW-4 NSS Restoration
What You Probably Know About The Automatic Transmission That Jeep PutIn The '87-'01 Cherokees is that it's one of-if not the-best slushboxes to leave the factory in a Jeep in the last 20 years. It has a decent overdrive and First-gear ratio and is known to outlast even the venerable six-cylinder engines.
What you might not know is that the AW-4 doesn't have a normal Neutral Safety Switch (NSS) but rather a goofy-looking one that controls backup lights, shift points, and overdrive engagement, as well as doesn't allow your Jeep to start in Neutral or Park.
If you're a Cherokee owner, the NSSgoing bad can be evidenced by checkengine codes, such as P0700 (Transmission Control System Malfunction) or P0705 (Transmission Range Sensor Malfunction)- and/or your backup lights aren't working, you have to wiggle the shifter a little or hold it in a certain position to get them to come on, or you have to wiggle the shifter fore and aft to get the Jeep to start, or it starts only in Neutral or only in Park, or won't shift into overdrive ... there are tons of symptoms.
Now, that's all well and good, but why are we prattling on about it? To get the replacement NSS even from NAPA (PN ECH NS5502), it is $339 as of this writing. Sure, you could find it for less, but do you want to cheap-out on a part that controls that many things? We decided to do just that, and for under $10 we had our NSS working like the day our high-mileage XJ left the factory. So, follow along as we show you how to save $329 when your NSS starts having issues.