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TCU code 45

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I have searched around a bit on the forums concerning this and found quite a bit of information on TCU codes but nothing specifically related to this one.

 

I own a 2000 OBW with 115K miles. We changed the transmission fluid and filter following suggestions on this forum about 4 weeks ago.

 

Just yesterday, the AT Oil Temp light started flashing consistently while my wife was on her way home from the store. When I drove the car that evening, no light and nothing weird when turning sharply. So, I didn't think much of it.

 

Today, while I was driving it home the light started flashing consistently again. I researched the topic on the forum and found a reference to the "Subaru TCU Secret Handshake". I found the procedures and the AT Oil Temp light flashed out a code 45.

 

I did some searching for this code and came across TSB #166602 which describes what my car does in the winter when driving slowly and the backend begins to slip. Although the harsh AWD engagement has been consistent the entire time we have owned the car (4 years), this is the first time the AT Oil Temp light has came on.

 

Does anyone have any insight into this issue?

 

Thanks in advance for any help.

 

MatrixOps

Code 45 Intake manifold pressure signal Detects open or shorted input signal circuit.

 

Sounds like you already searched and found this info, but here it is anyway:

Service Note:

Harsh AWD Engagement and TCU Code 45

1999-2002 All Models

You may encounter a 1999-2002 Subaru vehicle with a customer report of a loud bang emanating from the rear of the vehicle during slow-speed acceleration on ice or snow. This may be caused by the transfer clutch being engaged when the system detects wheel slippage.

 

Inspect the vehicle to see if a TCU Code 45 (intake manifold pressure sensor) is present. If so, first inspect the wiring and connectors as directed in the appropriate service manual. Next, confirm that the AWD system is operating correctly.

 

Replacement of the TCU may be needed to correct the problem. Please note that if the vehicle is also experiencing an ECM code for the intake manifold pressure sensor, replacing the TCU will not correct the problem.

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