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Discussion Starter #1 (Edited)
Hey guys, I've searched & read several threads on this issue already, but none seem to be similar to the issue i'm experiencing.

SMG pump & accumulator have already been replaced due to experiencing the same issues as several others with SMG failures (red cog of death, won't go into gear, car wont start, etc.)

We replaced the pump & accumulator, filled with new SMG fluid, performed the bleed procedure, dropped the car on the ground and the issues were still present. Car was still coming up with transmission fault message and would randomly not allow a gear to be selected. SMG pump was running almost constantly which leads to the assumption there is a leak somewhere. However, here is where it gets confusing (to me).

With the car OFF (ignition on), the SMG pump will prime to 65-70bar, and gradually drop to ~60bar over approx. 5 minutes. The pump will kick back on for about 2-3 seconds, prime up to ~70bar, and will continue this process. This seems to be considered "normal" behavior. With the car running, the SMG pump will be on almost constantly (barely maintaining ~60bar), until the car detects a fault and kills the SMG pump, which causes the hydraulic pressure to drop to 1bar in about 2 seconds. I also noticed the hydraulic fluid temperature was showing over 100°F, which seems very high compared to other posts I've read.

Just wondering if anyone has ever heard of this behavior before, or have any insights as to what the issue may be? Both SMG relays have also been replaced.

Thanks for your time!
 

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While running it will get way above 100F. Or did you mean 100C? But first let's be clear on what you replaced: was it the pump motor? And what is the actuator you refer to?

Post a video of how it sounds. And what codes are you getting.
 

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Discussion Starter #3
While running it will get way above 100F. Or did you mean 100C? But first let's be clear on what you replaced: was it the pump motor? And what is the actuator you refer to?

Post a video of how it sounds. And what codes are you getting.
Sorry, my bad. Meant to say accumulator, not actuator. I edited the original post to fix.

SMG pump motor and accumulator were both replaced. Fluid temp was over 100F.

I will take a video and post tomorrow!
 
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