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Posted

Hello all, my 2002 2500hd with the 6.0l and 4l80e stopped showing the correct gear. My first thought was to replace the NSS and after melting hot glue to change it, it is still broke. The truck will show park if you just get in and start it. When i pull the lever down it goes to reverse and stops unless i take the selector down to 1st gear, then the indicator rapidly moves down to first, and if you just click the truck into drive, sometimes the indicator will move down after a little bit of driving. The reverse lights will come on while in reverse whether or not the indicator shows reverse. The truck drives like normal, and doesn't shift any different. Also, the doors stopped auto locking and unlocking. Any help is appreciated! 

Posted

Maybe there is a problem with the NSBU (the plastic blob hanging off the driver's side of the 4l80e)?  If you get access to a more advanced code reader, that can get codes from the transmission, bcm and i/p, might give you an idea of what the problem is...

Posted
5 hours ago, davester said:

Maybe there is a problem with the NSBU (the plastic blob hanging off the driver's side of the 4l80e)?  If you get access to a more advanced code reader, that can get codes from the transmission, bcm and i/p, might give you an idea of what the problem is...

i replaced the NSS first and nothing happened. I just dont understand why the truck shows the wrong gear, if i put the lever into reverse, the indicator wont show reverse but the reverse lights will come on.

 

 

Posted

You could try installing a used instrument panel from a junkyard to see if it's the i/p that's gone bad (shouldn't be that expensive)

 

But an advanced code reader is probably what you'll need to figure it out, to avoid just throwing parts at it.

  • 3 years later...
Posted
On 2/13/2018 at 10:16 PM, Brendan Corr said:

i replaced the NSS first and nothing happened. I just dont understand why the truck shows the wrong gear, if i put the lever into reverse, the indicator wont show reverse but the reverse lights will come on.

 

 

Did you ever find out what was wrong with it ive got the same problem

  • 2 years later...
Posted
On 2/2/2022 at 7:50 PM, Hfjskdjfjjdjjdf said:

Did you ever find out what was wrong with it ive got the same problem

Hello,

I also have this exact same problem including the doors not unlocking when I put it in park. Even after doing the reprogramming steps a few times. I'm assuming it is connected to the gear indicator acting funny.

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