Transmission Problem

[cardr69]

I have a 2003 Silverado 2500 4x4 with a 6.0ltr and a 4L80E trans, was working fine, and now it won't start, when I turn the ignition key on the shifter indicator says it is in 2nd gear, then I was told buy the tranny guy that it probably is the neutral safety switch, replaced it and it stil registers that it is 2nd gear and still it does not run, can you or anybody help me strande at home with no other wheels (to do list approaching). Thanks

[gmtech4]

get it scanned if ya can ,you got problems .Ive never heard of that before.your gonna have to get a tech to diagnose it as throwing parts at it already burnt you .good luck .

[Gregorio]

I agree. Check for codes first.

 

However, if I was to guess, I'd say the gear selector is the culprit.

[gmtech4]

he changed it already

[Gregorio]

I guess I missed that

 

Well, I have never seen the dash indicator stuck on 2 but there are several reasons why a 4L80 stays in second gear and they are most if not all electronics related. Usually, the truck will start and everything appears normal except there is only second gear. There are a variety of sensors that the tranny relies on and if it loses signal or one is out of range, it will go into limp mode which is only second.

 

There are two potential problems that can cause this with inexpensive fixes. The first is poor electrical connections to the transmission. Unplug the TSS and TCS wires and check to make sure they are getting good connection. The second is a blown fuse for the transmission control solenoid. Check the fusebox for a blown TCS fuse. If that is the problem, you might have a bad TCS. They will run you about $60 at your local autoparts store. Another problem could be TSS itself but that is harder to diagnose without the right tools. They also cost about $60 but are a bitch to remove if the bolts are rusted.

[brims]

I guess I missed that

 

Well, I have never seen the dash indicator stuck on 2 but there are several reasons why a 4L80 stays in second gear and they are most if not all electronics related. Usually, the truck will start and everything appears normal except there is only second gear. There are a variety of sensors that the tranny relies on and if it loses signal or one is out of range, it will go into limp mode which is only second.

 

There are two potential problems that can cause this with inexpensive fixes. The first is poor electrical connections to the transmission. Unplug the TSS and TCS wires and check to make sure they are getting good connection. The second is a blown fuse for the transmission control solenoid. Check the fusebox for a blown TCS fuse. If that is the problem, you might have a bad TCS. They will run you about $60 at your local autoparts store. Another problem could be TSS itself but that is harder to diagnose without the right tools. They also cost about $60 but are a bitch to remove if the bolts are rusted.

 

But he can't even start it so he needs to do a diagnosis with a scanner to see what's up. So it's not driving in second, it's in second gear before he starts the truck.

[Gregorio]

I guess I missed that

 

Well, I have never seen the dash indicator stuck on 2 but there are several reasons why a 4L80 stays in second gear and they are most if not all electronics related. Usually, the truck will start and everything appears normal except there is only second gear. There are a variety of sensors that the tranny relies on and if it loses signal or one is out of range, it will go into limp mode which is only second.

 

There are two potential problems that can cause this with inexpensive fixes. The first is poor electrical connections to the transmission. Unplug the TSS and TCS wires and check to make sure they are getting good connection. The second is a blown fuse for the transmission control solenoid. Check the fusebox for a blown TCS fuse. If that is the problem, you might have a bad TCS. They will run you about $60 at your local autoparts store. Another problem could be TSS itself but that is harder to diagnose without the right tools. They also cost about $60 but are a bitch to remove if the bolts are rusted.

 

But he can't even start it so he needs to do a diagnosis with a scanner to see what's up. So it's not driving in second, it's in second gear before he starts the truck.

 

 

 

That's what throws me too. I've seen a few vehicles that start and only have second gear. If this wasn't a common problem on the 4L80, I would have said 100% that it was gear selector.