Hey, buddy... My friend has a 2000 Sierra with a 5.3 and a 4L60E. He only has first and second gear. It won't even go into third or forth. No slippage or anything, just the first two gears. Last week we had some high water, if you think that might have something to do with it. He had a dtc, so we ran a scan a few days ago, and got P0748-Pressure control solenoid valve circuit... Still poppin the same code...But his trans seemed to be trouble-free then... What's up???

 

you have definatly lost a solenoid!
i think its the # 32 solenoid!
****ty man!
there is a possibility to replace the solenoid and doesnt take much work to do... but better get a mech. to look at it first!

 

Well,exact diagnostics of these tranny solenoids are about as complex as your gonna find..in a nutshell,the pcm commands the pressure control solenoid to respond accordingly,and monitors the resistance of the solenoid to see if its commands are carried out.The solenoid moves X amount by varying amperage..around 0.1 amps to about 1.1 amps from low line pressure to high line pressure.The trans "shifts" as pressure changes.

The only way to check this type of circuit for sure is to have a scanner that will command high or low line pressure and check to see if the commands are carried out with an ampmeter.

that being said...you'll probably just want to change the pressure control solenoid and hope for the best.Also look closely at the BIG CONNECTOR on the rh side...the red/blk and lt blue/wht wires are the wires between the solenoid and pcm.those connectors tend to get nasty/oily and cause headaches.
no other codes at all?..i'd be te,pted to put the shift solenoids in as well while your in it.

 

Thanks, guys... I'll look at it in the morning.

 

Check all the connections unplug them clean if needed. My bud had the same thing happen after running thew some big puddles at work.

 

What in the name of sweet chocolate Christ is 'thew'?

Is 'Through' what you were going for there? [sm=happybounce.gif]


[sm=mail.gif]Looks like you just got a message from the grammar ****. He's coming back in a big way.