Hi all, I have a 2006 RL with over 300,000 km. The engine light intermittently comes on with the flashing D and check transmission light, along with other lights. ODB error code comes back as: P0796 - Pressure Control Solenoid C Performance/Stuck Off. Along with a lag in acceleration from stop and a jerk before what appear to be it getting into gear and then normal driving. Often the engine light and check transmission message goes away and the car runs smoothly, but will reappear a day or two later with above noted symptoms.

I contacted the local dealership in Toronto, Canada and asked for the part# that needs to be replaced. I was first advised that the pressure switch needed to be changed, ordered the part picked it up, but during pick up was chatting with a different individual who suggested that it might actually be the solenoid itself which is considerably more expensive and appears more challenging to replace and/or test as a DIY. So one of two parts that need replacing:

1. 28600-RKE-004 or 28600-RAY-003 = 4th (C) Clutch Transmission Fluid Pressure Switch
or
2. 28260-RDK-023 = A/T pressure Control Solenoid Valve C

I've looked at the manual/repair guide on replacing the two parts which appear to be next to each other and feel the switch should be easier to replace, but am concerned about attempting the solenoid that has joint pipes with filters, o rings, gasket etc (not to mention cost)

Has anyone experienced this error code and if so which of the above part was the culprit? Did you do it yourself? Something relatively straightforward as a DIY?

The car is old and I am buying a new one this fall, so just need the RL to get me through until then, so don't want to spend too much and wanted to fix this myself if possible. Also what's the risk of me continuing to drive it with the sticky shifting and error code?

I tried searching this topic on the 2G RL forums and didn't see too much info on P0796 nor what the cause or fix was. My apologies if I'm posting in the wrong area but would really appreciate any assistance from someone that had this issue.

Note: 4 months ago I had both the output and input shaft transmission speed sensors replaced along with tranny fluid and last week replaced a failed ignition coil.

 

As you stated, according to the parts graphic below it appears that #8 solenoid 28260-RDK-023 & the #11 28600-RKE-004 pressure switch(s) are near one another.



Included below is all I can find, in relation to the solenoid replacement, to give you an idea of what's involved with its repair:

A/T Clutch Pressure Control Solenoid Valve C Test

A/T Clutch Pressure Control Solenoid Valve C Test
1.Connect the HDS to the DLC (A).

2.Choose Clutch Pressure Control (Linear) Solenoid C in Miscellaneous Test Menu on the HDS.
3.Test the A/T clutch pressure control solenoid valve C with the HDS.
-If the valve tests OK, the test is complete. Disconnect the HDS.
-If the valve does not test OK, follow the instructions on the HDS.
-If the valve does not test OK, and the HDS does not determine the cause, go to step 4.
4.Remove the battery trim and left upper fender cover.
5.Remove the air intake duct and air cleaner housing.
6.Disconnect the A/T clutch pressure control solenoid valve C connector.

7.Measure the A/T clutch pressure control solenoid valve C resistance at the connector terminals.
Standard: 3 - 10 ohms
-If the resistance is out of standard, replace the A/T clutch pressure control solenoid valve C.
-If the resistance is within the standard, go to step 8.
8.Connect the negative battery terminal to the solenoid valve C connector terminal No. 2 and connect the positive battery terminal to the connector terminal No. 1.
-If a clicking sound is heard, the valve is OK. Reconnect the connector, and install all removed parts.
-If no clicking sound is heard, go to step 9.
9.Remove the A/T clutch pressure control solenoid valve C.

10.Remove the ATF joint pipes, O-rings, ATF pipe, and gasket.
11.Check the fluid passage of the solenoid valve for contamination.
12.Connect the negative battery terminal to A/T clutch pressure control solenoid valve C connector terminal No. 2, and connect the positive battery terminal to the connector terminal No. 1. Make sure the A/T clutch pressure control solenoid valve C moves.

13.Disconnect one of the battery terminals and check the valve movement at the fluid passage in the valve body mounting surface. If the valve binds or moves sluggishly, or if the solenoid valve does not operate, replace the A/T clutch pressure control solenoid valve C.
14.Clean the mounting surfaces and the fluid passages of the solenoid valve body and the transmission housing.
15.Install the 8 x 53 mm ATF joint pipe (A) with the filter side into its mounting hole (8).

16.Check the height (A) of the 8 x 53 mm ATF joint pipe (B) between the top (C) of the pipe and the solenoid valve body mounting surface (D). The height is about 7 mm (0.3 inch) If the height is over 7 mm (0.3 inch), push the pipe until it bottoms in the accumulator body.


17.Install the new gasket (A) on the transmission housing, and install the 8 x 34.5 mm ATF joint pipe (B) with the filter side into the transmission housing and 8 x 25.2 mm ATF pipe (D).

18.Install new O-rings (E) over the ATF joint pipes.
19.Install the A/T clutch pressure control solenoid valve C.
20.Install the air intake duct and air cleaner housing.
21.Install the left upper fender cover and battery trim.

The code is defined below:

Good Luck!

 

Thanks for the response @zeta very much appreciate it. I do happen to have the diagrams that you attached, but appreciate you attaching it to this thread as it may be helpful to someone else down the road with the same error code.

I guess replacing the solenoid first (or testing it) would be the first step before looking to replace the switch that many of the TL forums talk about. Do you know if that switch is linked with that specific solenoid? Just curious if that switch initiates the solenoid. I dont think I have any leads to connect to the battery to test the solenoid, so would likely have to go the replacement route. I've ordered an aftermarket solenoid for 1/4 of the price of the OEM, not sure if I'll regret that decision, but figured I'd give it a try. The OEM switch I picked up from the dealership I can always return if I dont use it, so I'll try taking apart the air intake box to see if I'll be able to access the Solenoid to test resistance or just straight replace without touching the switch.

Curious to see if anyone else has had this issue and what they did to address the error code.

Thanks again

 

@Omballs search https://acurazine.com/forums/search.php the "2G RL (2005-2012)" forum only, for "solenoid" and start reading - there's a bunch of older threads about the gearbox.