i dont know what these codes are? Help

p1596
p0123

 

No such thing listed for an 01. Is it a different truck you're working on?

 

P0123-THROTTLE POSITION SENSOR #1 VOLTAGE TOO HIGH

but that is for a gas engine. Still nothing on the p1596

 

no this is for my 01 the one that my sig is. I dont understand whats wrong with it. i realy need help. I work Mon. thru Fri. 8.5 to 5.5 so by the time i get out everything is closed.

 

Is the MIL on? Flashing? How is the engine performing compared to before the codes?
P0123 TPS Voltage too high
P1596 Speed Control Switch Always High

 

MIL is that the check engine light if it is no it is not on. I don’t know if the truck is running any different ill tell you this since I reset the APP I have noticed a little difference but some ppl are telling me that I might have to adjust it. I don’t trust myself to do that, I started noticing all this when I put the gauges on I noticed that the boost at cruse could be down at 5 I have even seen it drop down to 1 or 2. I also have a weird tranny problem I say weird because I can shut it off and turn it back on and it will shift fine. Some ppl told me that it was the brake switch, but I changed that and it is still doing it. What it is doing is that it won’t shift to the last gear so if I throw it in neutral and shut it off then turn it back on and then it would shift just fine. So like I say I don’t know what’s up with this truck. I have checked for boost leaks and it seems that I don’t have any. I am going to check that today again. The MIL I don’t know what that is. There is no blinking lights on my dash that I have noticed.

 

MIL = Malfunction Indicator Light (check engine light)

It is interesting you mention your 'weird' issue and having to turn the engine off/on. I stop for fuel, reset the overhead, and drive away. About 20% of the time, maybe less, the overhead isn't as quick to change as you might think it would be with only a few miles on the tank. Most of the time, it changes quickly when I have a few miles, and of course, not as much when I get some miles on.

Also seems to me the engine runs a bit different that 20%, not as efficient I think. If I pull over and shutdown/restart, it usually puts it in the 80% group and runs great. If I don't, it will run the 20% program no matter how long/far I drive.

I now have ~125k miles on it.

 

so what are you telling me to do?

 

Double check those codes if you will. Neither come up on the Dealerconnect website for your year/make/model. As for the tranny concern it sounds like a governor pressure sensor and transducer. Would probably want to get it checked out with a scanner to be sure though. Let us know!

 

well i had my tranny checked once with a computer but the guy found nothing. but it also did not act up when he checked it. he said everything was running good. I told the guy that it acts up some times but not all the time. like today i got on the truck to go to church and it ran fine after church it was fine, but then when i got home i turned it off did things at the house then left and i kind of felt that it acted up a little. I am not to sure becosue i never went over 40 i ussaly feel it when i hit 55 or 60 becouse thats when it does not want to shift. ill double check the codes and what ill do is when it acts up ill go to a tranny shop for them to plug it in then. ill let yall know what happens.

 

P0123 is APPS signal voltage too high
P1596 Speed control switch always high

Bad thing about the "key on/off" way of getting codes is that those dtc's could have been there a long time. It would be nice from a diag standpoint to see how many "starts" is on that 0123 code (DRB wins again!). If the cruise works basically disreguard the 1596. With the 0123 being "intermittant that leaves power/grounds, signal circuit, return circuit, the sensor itself, or even an ECM (that would be a first, but still a possibility that has to be thrown out there).

 

so how do i fix that

 

ok I replaced the APPS but it is still throwing the P0123 code. The truck runs alot better then what it was before thats for sure.

 

Voltage always high, seems like computer is seeing a higher voltage than expected on a signal wire. I recall a fix somewhere on running additional ground from apps to neg. battery. The MAP, WIF, IAT, ECT, EOP and APPS are all feed 12v(?) by engine control mod. Have seen water in connector bleed enough voltate across circuit to induce problem.
good luck.

 

man thanks i did not expect an answer.