Partial ABS Shutdown

Depending on the trouble code detected, the ABS ECU partly or completely disables the ABS functionality. The trailer ABS system, for vehicles that only have one modulator, are disabled by any single fault. In the case of vehicles with two or three modulators, depending on the trouble code, the trailer ABS system may still provide some level of ABS function on axles/wheels that are not affected by the fault, but the ABS indicator lamp will remain on. In cases where the ABS is completely disabled, the vehicle reverts to normal braking (without ABS interventions). Always repair ABS shutdowns at the earliest opportunity.

ECU Diagnostic Trouble Codes

All ABS functions are completely disabled. The system reverts to normal braking.

Voltage Diagnostic Trouble Code

While voltage is out of range, the ABS functionality is disabled and the system reverts to normal braking. When the correct voltage level is restored, full ABS is typically available again. The operating voltage range is 8.0 to 16.0 VDC.

BLINK CODE DIAGNOSTICS

The TABS-6 module provides diagnostic and configuration functions through blink code diagnostics. This means that the technician, even without diagnostic tools, can read a series of ABS indicator lamp blinks to diagnose the trouble codes being generated.

The blink code diagnostics mode is entered by providing constant power to the ignition circuit and toggling the brake light power input three times. With a parked towing vehicle attached, this is done by applying ignition power and after the power up sequence is complete, depressing and releasing the brake pedal three or more times, see below for chart.

Depending on the blink code mode activated, the TABS‑6 module will blink the trailer-mounted ABS indicator lamp to display: active fault codes; fault code history; ABS configurations; and odometer mileage. Blink code diagnostics can also be used to reset active fault codes.

With Ignition Power	Blink Code
Applied, Cycle Brake	Action
Light Power
3 times	Display Active DTCs

4 times	Display Inactive DTCs

5 times	Clear Active DTCs

6 times	Display Configuration

7 times	Display Odometer Mileage

8 times	Reset Configuration

CHART 5 – blink code information

Wait until after the modulator chuff test before activating the brake light power. Following a single display of all available messages, the ABS indicator lamp will remain on for five seconds and then return to normal operating mode. Blink code diagnostics can only be activated following a power-up, where wheel speeds have not been detected. If the vehicle moves during blink code diagnostics mode, the module will cancel the blink code diagnostics and return to normal operating mode.

Blink code diagnostics must be activated within the first 15 seconds of ignition power being applied.

If brake light power is continuously applied for greater than five seconds, blink code diagnostics will be disabled until the next time the ignition power is cycled.

Display Active Diagnostic Trouble Codes

To display active codes, apply ignition power and depress / release the brake pedal 3 times within 15 seconds. Following activation, there will be a 5-second delay followed by a blink code display of all active fault codes. (See pages 10-12 for more information.)

Display Diagnostic Trouble Code History

To display trouble code history, apply ignition power and depress / release the brake pedal 4 times within 15 seconds. Following activation, there will be a 5-second delay followed by a blink code display of all history fault codes. (See pages 10-12 for more information.)

Reset Active Diagnostic Trouble Codes

To reset active codes, apply ignition power and depress / release the brake pedal 5 times within 15 seconds. Following activation, there will be a 5-second delay followed by a blink code message of:

1-1, (System Fully Operational - No Codes Detected) or a blink code display of all remaining active fault codes.

The ABS indicator lamp will stay on if active DTCs are still present.

Resetting active fault codes with blink code diagnostics does not clear information from trouble code history. Both blink code diagnostics or diagnostic tools can retrieve trouble code history, but only diagnostic tools can erase this information.