Pinpoint Test G: Tire/Axle Out of Acceptable Operating Range

WARNING: This page is about a different variant/trim than selected.

Refer to appropriate SYSTEM WIRING DIAGRAMS - EDGE or SYSTEM WIRING DIAGRAMS - MKX article for All Wheel Drive (AWD) schematic and connector information.

Normal Operation

The all wheel drive (AWD) system continuously monitors vehicle conditions and automatically adjusts the torque distribution between the front and rear wheels. During normal operation, most of the torque is sent to the front wheels. If wheel slip between the front and rear wheels is detected or the vehicle is under heavy acceleration, the AWD system increases torque to the rear wheels.

DTC P1635 Tire/Axle Out of Acceptable Range - When the 4X4 control module detects inappropriate mini spare or road wheels/tires (greater than 5% at one wheel) installed, this DTC is set.

This pinpoint test is intended to diagnose the following:

Wheels/tires
Wheel speed sensors
ABS module
4X4 control module

PINPOINT TEST G: TIRE/AXLE OUT OF ACCEPTABLE OPERATING RANGE

NOTE: This test must be carried out on a hard surface in an area without traffic.

NOTE: Carry out Inspection and Verification as outlined before carrying out this pinpoint test.

G1 CHECK THE RECENT TIRE USAGE
- Check with customer about recent tire usage or installation.
- Has a tire been installed on the vehicle recently that was not originally supplied with the vehicle?
1. YES : INFORM the customer to only use tires of the type supplied with the vehicle. CLEAR the DTCs. REPEAT the self-test.
2. NO : Go to G2.
G2 CHECK TIRE SIZE AND BRAND
- Check the tire size and the brand of tire.
- Are all 4 tires the same size and brand?
1. YES : Go to G3.
2. NO : INSTALL tires that are the same size and brand. INFORM the customer to only use the same size tires and brand. CLEAR the DTCs. REPEAT the self-test.
G3 CHECK TIRE AIR PRESSURES
- Check the air pressure in all 4 tires.
- Are all 4 tires at the recommended air pressure?
1. YES : Go to G4.
2. NO : ADJUST the tire air pressures. CLEAR the DTCs. REPEAT the self-test. INFORM the customer to maintain the correct tire air pressure.
G4 CHECK FOR CORRECT WHEEL SPEEDS
- Connect the diagnostic tool.
- Enter the following diagnostic mode on the diagnostic tool: DataLogger - 4X4 Control Module
- While driving the vehicle at 48 km/h (30 mph), monitor the following wheel speed sensor PIDs:
  - Left Front Wheel Speed Sensor (LF_WSPD)
  - Left Rear Wheel Speed Sensor (LR_WSPD)
  - Right Front Wheel Speed Sensor (RF_WSPD)
  - Right Rear Wheel Speed Sensor (RR_WSPD)
- Are all 4 wheel speeds within 3 km/h (1.8 mph) of each other?
1. YES : Go to G5.
2. NO : The ABS module is sending invalid wheel speed data to the 4X4 control module. REFER to VEHICLE DYNAMIC SYSTEMS article for additional ABS module diagnosis.
G5 CHECK FOR CORRECT 4X4 CONTROL MODULE OPERATION
- Disconnect: 4X4 Control Module C281
- Check for:
  - corrosion.
  - pushed-out pins.
- Connect the 4X4 control module and make sure it seats correctly.
- Operate the system and determine if the concern is still present.
- Is the concern still present?
1. YES : INSTALL a new 4X4 control module. REFER to 4X4 CONTROL MODULE . CLEAR the DTCs. REPEAT the self-test.
2. NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.