Efan install and now speedo says transmission stuck in 1st
06-15-2007, 04:51 AM
#21
Originally Posted by RandomHero
Here's a decent but unfortunate update:
We've tried everything I can think of. I've spend a good 20 hours(that's not an exaggeration) searching for people who have had similar problems. The truck is now at the dealership because I have run out of ideas.
We've tried:
unhooking battery overnight
checking cables to pcm/tcm
disconnecting efans
checking a/c wire
plugging back in clutch fan
check fuses for everything relevant
The truck:
Won't read codes(even the dealer can't)
It goes in and out of limp mode
The CEL comes on and off(more on than off)
The fans run fine when the truck is on(a/c commands them right too)
The speedo also doesn't work and the gear indicator is stuck on "1" even though it will work in all gears.
Here's the most interesting thing:
When I went to check some of the cables on the PCM, it gave me a small shock. I have NO IDEA what this means but I'm sure it's not good.
We've tried everything I can think of. I've spend a good 20 hours(that's not an exaggeration) searching for people who have had similar problems. The truck is now at the dealership because I have run out of ideas.
We've tried:
unhooking battery overnight
checking cables to pcm/tcm
disconnecting efans
checking a/c wire
plugging back in clutch fan
check fuses for everything relevant
The truck:
Won't read codes(even the dealer can't)
It goes in and out of limp mode
The CEL comes on and off(more on than off)
The fans run fine when the truck is on(a/c commands them right too)
The speedo also doesn't work and the gear indicator is stuck on "1" even though it will work in all gears.
Here's the most interesting thing:
When I went to check some of the cables on the PCM, it gave me a small shock. I have NO IDEA what this means but I'm sure it's not good.
Sounds like there may be some corrupt parameters on the PCM, tell him to make sure the dealer puts in a new PCM!
BE SURE anytime you are dealing with the PCM disconnect the negative side of the battery.
06-15-2007, 10:45 AM
#22
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Wow the pcm cable shocked you? that sounds kinda bad there bro. I would think something is majorly wrong there. Maybe the pcm is bad? Maybe a reflash with updates is in order?
06-15-2007, 06:37 PM
#23
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Where is the ground for the fans? Have you checked your ground offset voltage? When you use an existing ground for an add on accesory it can sometimes back feed into the pcm and could have fried one of the boards. Did you leave the battery hooked up during install of the fans? Some ecm's will blow just by removing the connections with the battery's hooked up. Just some ideas.
Edit: Have you checked for power,ground and data link wiring at your diagnostic connector?
Edit: Have you checked for power,ground and data link wiring at your diagnostic connector?
Last edited by 99RCSB; 06-15-2007 at 06:42 PM.
06-15-2007, 09:50 PM
#25
Ok guys he got the truck back. Here's the result:
The TCM, PCM and ECM were all replaced. He lost his tune from Vector Motorsports, but I'm sure they'll retune it for him.
Also they said the TCM cable was "broke" although I didn't even touch that cable when I installed the fans.
The truck now works fine with the exception of the fact that he has no cooling fan(clutch or electric).
I think it was the fact that I never disconnected the negative battery harness. Yes I know, stupid me, I have no idea what I was thinking. I was so excited to see this thing run that I totally skipped that step. All in all I'm kicking myself for that one little error knowing that it was probably the cause of all this grief.
I still hope he wants to put efans on it though because they made a HUGE difference on mine and the tbss' scream as it is and PCM4less made like 15/15 hp/tq.
The TCM, PCM and ECM were all replaced. He lost his tune from Vector Motorsports, but I'm sure they'll retune it for him.
Also they said the TCM cable was "broke" although I didn't even touch that cable when I installed the fans.
The truck now works fine with the exception of the fact that he has no cooling fan(clutch or electric).
I think it was the fact that I never disconnected the negative battery harness. Yes I know, stupid me, I have no idea what I was thinking. I was so excited to see this thing run that I totally skipped that step. All in all I'm kicking myself for that one little error knowing that it was probably the cause of all this grief.
I still hope he wants to put efans on it though because they made a HUGE difference on mine and the tbss' scream as it is and PCM4less made like 15/15 hp/tq.
07-14-2012, 03:33 PM
#28
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My 06 TBSS is doing the samething right after I Installed the dual elect fans it says its stuck in 1st and is in limp mode, only one of my fans is turning on right now I just got the a/c done on it I am gonna try and see what happens, need some help please thanx
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