2002 Explorer, O/D light flickering, P0796

BLittle500 · November 9, 2012

Hey guys,

My wife called today in a panic, her 02 Explorer seems to have a trans issue, and I'm not the man for the job. The O/D light is flickering (no way its a flash code, way way to fast) and I pulled a P0796 out of it with my code reader. Any ideas, known concerns, things to look for?

2002 Explorer

4.0, 4X4

Thanks in advance,

Brandon

Keith Browning · November 10, 2012

Looks like a straight forward shift solenoid open circuit fault. I would simply follow the pinpoint tests in the WSM - should lead you to the problem. I am not aware of any common issues related to this DTC...

Jim Warman · November 10, 2012

In the DTC chart, the code P0796 is followed by a pair of asterisks indicating a footnote that reads "**May also be generated by some other non-electric transmission hardware system.".

Now, I don't get to work on many 5R55s but memory tells me that one should be able to use the IDS/WDS/NGS to change the solenoid state and listen for the click (KOEO) or watch a change in trans pressure (KOER). Also bear in mind that, if you are commanding more than one solenoid at a time, the software will not allow you to command solenoids that would conflict with each other at the same time (caution - memory thing).

This whole deal may result in a need to go to symptom driven diagnosis.

I also recall there being many TSBs for various trans issues so running OASIS might be a wise thing to do early in the process.

ktmlew · November 10, 2012

Upper valve body gasket starting to blow out?

Matt Saunoras · November 14, 2012

Line pressure gauges are your friend. The PCC tap is on the right side behind the intermediate servo cover. You should be able to control the PCC through IDS and watch the line pressure to verify it's what's commanded. I've diagnosed a few harsh engagements this way when the solenoid body is the issue.

Solenoid bodies are pretty common in 5R55w/s. I'm not sure in this instance though, the dtc kind of leads towards a solenoild open internally.