Johnny HotFoot

Please help!
I've read alot but haven't found the answer yet...

If I don't turn the OD (overdrive) OFF when I start, my 2010 Rubicon will make jerky transitions into and out of overdrive and after a short while will throw the CEL (check engine light) .... but if I turn it off I have no issues..... my Jeep has 111,000 miles on engine, and about 80,000 on the trans and never had any issues ever.

Thanks in advance.... I'm hoping I can fix this myself

karls10jk

Well what does the code indicate? Seeing as it's transmission related, you may need more than just the AutoZone scanner to pick it up.

Johnny HotFoot

Drove to work without turning O/D Off, sure as shit the Jeep was sending me all kinds of feedback, jerky downshifts and late upshifts, running way high rpm's on freeway, and the CEL came on near end of drive, tried to get the code being thrown but I messed up and it cleared without me seeing it... so now I'll disconnect the battery for 30 seconds to reset CEL and try again...

My problems all seem to go away by turning off the overdrive.... surely others have had this problem and can chime in with what fixed it???

Johnny HotFoot

ronjenx

Can your code scanner find Pending Codes?

Here is some info for the code you have:

P1790 Fault Immediately After Shift

Theory of Operation
This DTC is not stored alone. It is stored if a Gear Ratio DTC is detected immediately after shift. The existence of DTC P1790 indicates a mechanical or hydraulic (not electrical) related problems. It should be noted, however, that all mechanical problems don't necessarily result in DTC P1790. When this DTC exists, diagnosing the system should be based on the associated DTC and only mechanical causes should be considered.

• When Monitored: After a Gear Ratio Error code is stored.
• Set Condition:After a Gear Ratio Error DTC has already been set. The DTC is set if the fault happened within 1.3 seconds of a shift. The DTC set time will vary from 1.214 seconds to 15 seconds.
• This DTC is set along with a Gear Ratio DTC. Perform the appropriate test for the Gear Ratio DTC stored.
• NOTE: Check Pending DTCs or 1 trip failures if there are no Active or Stored Gear Ratio DTCs.

Johnny HotFoot

"The existence of DTC P1790 indicates a mechanical or hydraulic (not electrical) related problems."

Ok, so??????

ronjenx

You quoted only one sentence from the post.
The entire rest of the post suggests you look for a gear ratio error code; either pending, or a 1 trip failure.
If the scanner you used doesn't display pending, or a 1 trip failure codes, perhaps a trip to the dealer is in order.