Allison 5sp: p0742 with bt lockup box.

strongsperformance

2002 sierra cc dually
Jan 14, 2011
78
0
6
lake orion michigan
I installed a hsp twin kit this past weekend and installed atp tuning. Hopped in it tonight and it threw a p0742 code with no reverse. But if I don't turn on the lock up box and run factory tow haul then it works fine. But if I turn on auto (blue light) it will lock converter right away (green light) then turns blue when brakes are applied then completely off when sitting at light it will throw a code during this time.
Anyone have similar problems?
I'm thinking either bt box messed up or trans is messed up telling tcc to lock.
I have built trans with 80k miles on the build.
Thanks guys
 

strongsperformance

2002 sierra cc dually
Jan 14, 2011
78
0
6
lake orion michigan
No
I've been running the box for about a month now.
I hopped on truck pretty good to about 90mph then I let out of it. The trans acted like it needed to shift even after I showed to 60. I noticed my lockup box in the green still. No matter what I do it I can not turn it off. I need to shut off truck and restart it.
If I drive in t/h is fine. But turn on auto mode on bt box then it locks and throw code rather soon. And I can not turn off box at all until key is cycled.
thanks
 

Mike L.

Got Sheep?
Staff member
Vendor/Sponsor
Aug 12, 2006
15,681
232
63
Fullerton CA
I told you what to do. Shut the box down till you get ahold of Ben. There is a glitch in the box.
 

strongsperformance

2002 sierra cc dually
Jan 14, 2011
78
0
6
lake orion michigan
Mike
thanks for the advice. I left Ben a message and being easter weekend I figure it will be a bit before I get a return call. So I was looking for a possible reply from someone with similar issues.
I am going to drive it tomorrow with box off and try to log it to see what trans is doing.
Thanks again for the advice
 

Awenta

Active member
Sep 28, 2014
4,090
2
38
CT
I agree with Mike. I know some other boxes can throw codes from constantly locking and unlocking. Bens shouldn't, he'll take care of you.

Sent from my SM-N910V using Tapatalk
 

strongsperformance

2002 sierra cc dually
Jan 14, 2011
78
0
6
lake orion michigan
Well I took truck out for drive most of the day. Running just normal mode and tow/haul it works great.
If I try to run auto on the lockup box it will lock ad soon as I hit 2nd great. So it must think I'm 95% in the throttle and then throws a p0742 with no reverse.
I will get with been eventually but I'll stop running it.
Thank you
 

CaptPhil

Active member
Sep 10, 2011
1,012
0
36
Delaware
sounds like you have a connection problem then, probably with the wire that connects to the throttle assembly.
 

OregonDMAX

NOT IN OREGON, NO DURAMAX
Apr 28, 2013
3,964
8
38
36
Goodyear, AZ
I had a somewhat similar issue, not with the trans issues but with the box locking and unlocking just like you described and so I emailed Ben and he got me squared away with an updated box with a newer version in it and its been fine ever since. Bit since you are having the code thrown and the shifting issues you issue might be different.
As suggested where is your power tapped into, sounds crazy but it makes a huge difference in operation.
 

strongsperformance

2002 sierra cc dually
Jan 14, 2011
78
0
6
lake orion michigan
Not sure what is powering it. I followed directions and found power at bcm plug.
today I checked wire at pedal and all was good. I checked codes with efilive and found p1272 and p1271 I cleared them and now everything's great. Switch works like it should. But I have throw the code a few times since but I think they are what is called 'ghost codes' from the bt box.
Idk:confused:
 

duratothemax

<--- slippery roads
Aug 28, 2006
7,139
10
0
Wyoming
Sorry everyone, Ive been away on vacation all week and havent gotten back to work until today.

Can you please send me an email? Ill help you get the issue worked out right away.

[email protected]

Ben
 

strongsperformance

2002 sierra cc dually
Jan 14, 2011
78
0
6
lake orion michigan
Update: solved problem.
after rewiring kit and swapping power points the problem still remained the same.
I ended up running a solid ground from battery and a fused positive from battery to a relay that is triggered by ignition "0" from interior dash fuse panel.
thank you
box works awesome. Love auto mode