I have an 06 sport coupe, recently the ABS, Slip, VDC, RAS lights came on. The scan tool extracted C1137, C1156 codes. These codes are for the RAS steering angle sensor circuit. Voltage measurement at the RAS controler indicated the sensor, (which is a dual sensor) inputs were grossly out of balance. Reasonable indication the sensor is bad. Sensor replacement is the course of action I chose to peruse.

The rear steering angle sensor is not available. The RAS assy that contains the sensor is $4k from the dealer. So I found a unit at a salvage yard and installed. I replaced the entire unit (jack assy), so as not to void the warranty from the salvage yard.

I have installed the replacement unit, hooked up and the problem persists. I have not explored any further. It appears the controller or wiring harness/connectors are bad. I checked the replacement unit before install. It was mechanically centered, both sides of the sensor were balanced, and the drive motor checked good.

Unfortunately I do not have a bi-directional scan tool to monitor what the controller thinks it is seeing.

Any words of advice? Tips?

 

There is a self-diagnosis you can put the RAS/HICAS system in that will flash the error on the dash (ras light flashes a certain code like how OBD1 used to work). I think the self-diagnosis mode was to start the car then turn the steering wheel left/right five times then pump the brake pedal 5 times. Gotta do it fairly quick so START/left/right/left/right/left/right/left/right/left/right then brake/brake/brake/brake/brake.

I suspect that the issue wasn't your steering angle sensor, the self-diagnosis will tell you exactly which part of the system isn't working properly. You can manually work the motor by applying 6v to it via a battery series harness and 4x AA batteries, there are steps in the FSM. When I had a bad RAS actuator motor I used this method to verify the motor was actually not working.

C1137 is a brake system code that's just saying "RAS system isn't functional".

C1156 shouldn't be a valid code for the 2006 coupe though, are you sure your scanner supports ISO protocol 9141-2 ? I've seen people report that code when their OBD2 scanner didn't have the correct protocol for this vehicle. Normally that code is used for a steering angle sensor but there are specific codes pertaining to the RAS steering angle sensor. I suspect your scanner is misinterpreting the data and you have something like a failing wheel speed sensor or the clock spring steering angle sensor.

 

The self-diagnosis error code chart was in the FSM section STC - Steering Controls, iirc.

 

I think the controller is bad, I can't get it to go into diagnostic mode. Also, I can read the sensor voltages at the controller, and they are correct, +12v, and brake switch input good also.

Is there a difference in the HICAS controllers for the M45 and G35? Or are they the same controller with different mounting brackets?

 

I got an 06 g35 coupe 6MT and it has hicas .but every time I turn the key switch to “ON” the HICAS component rattles and the two axles going to each side seems to go in and out and makes car slightly shake . What could this be ? Is something wrong ? SHould I stop driving it . I have no check engine light . Please help. I have video of it but won’t let me upload

 

Post video to YouTube then paste link here.

 

Here is the following link to the videos I made with these issues there should be two of them in my channel

 

 

Sounds like the actuator broke, I would remove the RAS assembly and start disassembling it, I'm betting the R&P gears are all chewed up.

 

What would be the best solution to fix this ?is it still safe to drive it ? It’s my daily driver to get to work ..