I have a 2007 IS350 with 160k. My p/s light came on when backing up in my driveway. I turned it off and it went away, drove it the next day and it happened while driving. Its been a couple of months and it either does it when i turn the car on, hit a bump or just randomly while driving. I did mess with the module, but never unplugged it to try and change out my upstream o2 sensors. Any ideas before i buy a module or rack and pinion. Thank you.

 

I personally wouldn't jump to hardware replacement when it works intermittently. Disconnect the battery and Disconnect the controller under the battery and also the connections at the R&P.

Have some electrical contact cleaner and some dielectric grease for the assembly. The PS ECU has some tricky contacts. When you do the right action, the connector will come right off. It is not intuitive!!!

IIRC there is a small black tab you pop up with a pick, flip the bayonet and the connector will partially disengage. Then it escapes me, but you push something else to allow the bayonet to fully flip and detach.

Unless a battery lost acid there, I would start under the car first. JM2C

 

Fixed. Loose plug.

 

Excellent.
Which one? Where at?

 

On the steering module. The plug on the passenger fender side.