1998 k1500 4l60e
Thread Starter
Registered User
Joined: Oct 2014
Posts: 7
Likes: 0
1998 k1500 4l60e I am getting a p0758 code which is shift solenoid b electrical. I have changed all 4 solenoids, internal wiring harness, ignition switch, pcm and checked resistance between pcm and trans. Could the pressure manifold switch cause this problem.
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
Some people have reported P0758 when running a high stall converter. Are you? Correction: A high stall might cause a P0756 (see below).
They then use a tuner to disable this code.
I am not aware of a bad pressure switch manifold causing this code, but it can cause very strange problems that make no sense.
They then use a tuner to disable this code.
I am not aware of a bad pressure switch manifold causing this code, but it can cause very strange problems that make no sense.
Last edited by mrvedit; Oct 13, 2014 at 06:47 PM. Reason: Correction on the code number
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
Researching this further, I see that it is P0756 (Solenoid B Performance) that is sometimes caused by a high stall converter.
P0758 (Solenoid B Electrical) seems to an electrical continuity problem.
Since you already replaced the solenoid, internal harness and even PCM, you have covered the most obvious bases.
I would drop the pan, turn on the ignition and check the voltage on the "ground" side of Solenoid B. If there is a bad connection in the path to the PCM, the voltage might be higher than the 0.5 volts (or less) that I would expect. Obviously the other side of the solenoid should be at +12 volts. Kinda grasping for straws here, but beyond that I am at a loss. If the trans is shifting fine, you might just tune it out.
P0758 (Solenoid B Electrical) seems to an electrical continuity problem.
Since you already replaced the solenoid, internal harness and even PCM, you have covered the most obvious bases.
I would drop the pan, turn on the ignition and check the voltage on the "ground" side of Solenoid B. If there is a bad connection in the path to the PCM, the voltage might be higher than the 0.5 volts (or less) that I would expect. Obviously the other side of the solenoid should be at +12 volts. Kinda grasping for straws here, but beyond that I am at a loss. If the trans is shifting fine, you might just tune it out.
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
Most diagrams show this as "Pin B" not pin 4:
https://ls1tech.com/forums/automatic...lems-help.html
http://www.msgpio.com/manuals/mshift/wiring.html
Sounds like you are well on your way to figuring this out. Perhaps you can find that wire near the PCM and check voltage there. (I use a tiny sewing needle to piece the insulation and put a alligator clip on the needle.)
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo Thread Starter
Registered User
Joined: Oct 2014
Posts: 7
Likes: 0
Drove the truck while checking voltage at pcm 1-2 0.384-0.398 volts shifts into 3rd 13.96-14.02 volts. Manual shift back to 2nd back to basic no voltage manual shift to 3rd back to basic 14 volts.
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
So, you are saying that the trans shifts correctly and the voltages are correct. If you clear the code, does it come back immediately, the 1st time you shift through the gears, or at some random later time?