Transmission code P0748

2004 KIA SORENTO

150,000 MILES • 3.5L • 6 CYL • 2WD • AUTOMATIC

BCMULLEN95

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249 POSTS
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Just replaced the transmission with a used transmission. Replaced the filter and flushed out lines before adding fluid. The car slips in first gear only except when you put in D1. Looking for the start point to find out what my issue may be.

Mar 5, 2020 at 5:23 AM

KASEKENNY

CERTIFIED EXPERT
18,907 POSTS

I suspect you have a solenoid issue. The fact that it does not slip when putting it in D1 shows that the mechanical clutches are capable of operating properly. This puts us to the control side of the transmission.

I attached the info and testing of the solenoid. I would suggest starting with this and see what you find.

Let me know if you have questions and we can go from there. Thanks

Images (Click to enlarge)

Mar 5, 2020 at 3:09 PM

BCMULLEN95

MEMBER
249 POSTS

I tested the solenoids, not quite sure of my results from testing the normal open or normal closed. The resistances are within specs. What I did is swap the solenoids from the old transmission to the replacement transmission. The P0748 is no longer showing up, however I still have P0700. Would I need to reset or relearn the replacement transmission to the car?

Mar 11, 2020 at 1:47 PM

KASEKENNY

CERTIFIED EXPERT
18,907 POSTS

Unfortunately this one will need more testing as well. That is good that the P0748 is gone however, we need to make sure the ECU is okay. I attached the testing and connector pin out charts so you can find the pins.

Run through this and see what you find. Thanks

Images (Click to enlarge)

Mar 11, 2020 at 5:26 PM