ABS pump kicks in for no reason on left turn???

[monkeyboyx]

ABS pump kicks in for no reason when turning left quickly or acceleration through the turn. Only happens on a hard left turn. Replaced both front sensors a few months ego and still no change. Replaced the two rear sensors yesterday. One was routed wrong through the suspension and the cable looked damaged. No go... still does the same dam thing. You feel the abs kick the paddle and it almost sounds and feels like its the driver front wheel. Or maybe it's sound of the pump. Idk anymore. Only does this for about 5-10 seconds. Apology if this been answered before. Was thinking of pulling the ABS fuse and taking it for a test drive.

(No abs codes, no abs, traction, stability light)

MKS, AWD, TC.

 

[krewat]

Maybe your left front tire is slipping Is the traction control light blinking when it does this?

Traction control uses the ABS system to apply the brake to the wheel that's slipping.

 

[SHOdded]

I have heard of one instance where you start from a stop, accelerate hard and turn at same time. It feels like the car conks out for a second, then resumes its' path. Anything similar? Could be due to torque management.

 

[Butcher]

Does your turning signal cancel automatically when turning left?

 

[monkeyboyx]

Well it did it to me again. Left turn, light turns green, stepped on the gas and traction light kick on for a sec or two. I feel the pedal kick, hear the pump and its using the front brakes to slow me down. Mind you I'm not driving like a bat out out of ****. Yes I know the system will kick in to save you when you are being stupid but this is not it. It should not be kicking in and especially only on a left turn. Going to look at the front left wheel in the next day or so. Maybe the abs sensor, tone ring or bearing issue.

 

[SHOdded]

Also check the suspension on both sides. Maybe a leaking shock or damaged sensor? Or simply a recalibration of the VDM?

Overview

The semi-active suspension dampening provides improved handling, comfort and stability by continuously adjusting the adaptive shock absorber force to the current road and driving conditions.

Vehicle Dynamic Suspension

The VDM is connected to the HS-CAN to communicate with the ABS module, the PCM and other systems. With the information received the VDM monitors the heave, roll, pitch, cornering, braking and acceleration of the vehicle. Based on that information the VDM calculates the best action for each valve solenoid.


Component Description

Vehicle Dynamics Module (VDM)

The VDM monitors all sensor inputs and all HS-CAN messages that relate to the vehicle dynamic suspension and then directly controls the valve solenoids. The VDM sends an individual electrical current to each valve solenoid to control the amount of damping required.

When a new VDM is installed, the module must be programmed with the vehicle configuration information. For additional information on module programming, refer to Section 418-01 .

When one of the following components is installed new, the VDM requires calibration.

• VDM
• Suspension height sensor
• Front lower control arm
• Front strut assembly
• Rear lower control arm
• Rear upper control arm
• Rear wheel knuckle

The calibration procedure is required for the system to learn the "zero-position" of the vehicle which means the vehicle must be on a level surface, must not be moving and cannot contain any passengers or cargo. The calibration procedure is carried out using a scan tool.

Height Sensor

The height sensor uses a potentiometer to send a variable amount of voltage back to the VDM . The sensor has 3 circuits, one circuit is for the 5 volt sensor supply, one circuit is for sensor ground and one circuit is for the sensor output.

Valve Solenoid

The VDM uses a PWM output to control the valve solenoid. The solenoid will open or close the valve depending on the amount of current supplied by the VDM . The higher the current, the more the valve is opened, resulting in a "firm" suspension feel.

SYMPTOMS

The stability/traction control indicator "sliding-car icon" is always/never on

• IPC concern
• ABS concern

• RETRIEVE all ABS module DTCs and REFER to the ABS DTC Chart. If no ABS module DTCs are present, REFER to Diagnosis and Testing in Section 413-01 .

ABS false activation, ABS too sensitive, ABS activates on normal stop

• Front/rear suspension concern

• ELIMINATE the front/rear suspension as the cause of the problem. REFER to Section 204-00 .

• RCM mounting

• CONFIRM the RCM is mounted correctly. REFER to Section 501-20B .

• Loose wheel speed sensor/excessive air gap

• INSPECT wheel speed sensor for looseness or excessive air gap. TIGHTEN or INSTALL new as necessary. REFER to Wheel Speed Sensor — Front and/or Wheel Speed Sensor — Rear .

• Wheel speed sensor magnetic strip (encoder) damaged, rusted or contaminated with foreign material

• INSPECT the encoder for damage, rust and foreign material. CLEAN, REMOVE foreign material or INSTALL new as necessary. REFER to Wheel Bearing and Wheel Hub in Section 204-01 or Section 204-02 .

• Parking brake shoes out of adjustment (dragging)

• CHECK and if necessary, ADJUST the parking brake shoes.

 

[SHOrod]

If you can find someone with a professional scan tool that has the ability to watch the ABS sensor data in real time, then duplicate the issue, that should help determine what's happening. When I've encountered things like this in other cars, typically what I'd find is a sensor that drops or jumps in reading very rapidly. In those 3 or so cases (I only do this as a hobby, not professionally) the issue was caused by corroded wires for a wheel speed sensor and the issue was more pronounced when the air was humid or after a rain.

-Rod

 

[zak]

Check your tone rings bet one is rusted underneath and split