Rough Road Signal: Description

The SLABS/ABS control module transmits a PWM signal indicating rough road for misfire detection disablement. The ECM has input diagnostics for this signal. See Fig 1 .

There are three plausibility checks of the PWM signal during which a fault is detected if:

1. The PWM signal is greater than a threshold indicating an electrical short to battery positive.
2. The PWM signal is less than a threshold indicating an electrical short to ground.
3. The PWM signal is greater than 44.92% but less than 55.08% indicating an error with the SLABS/ABS control module.

Fig 1: Rough Road Signal DTC Testing

Courtesy of LAND ROVER NORTH AMERICA, INC.