Bendix Commercial Vehicle Systems TABS-6 ADVANCED SINGLE CHANNEL User Manual

Page 30

SECTION D: TROUBLESHOOTING THE

POWER SUPPLY

Turn off the power to the module,

disconnect the 18-pin ECU

connector.

Check for high resistance

(corrosion, wire/connector damage

or improper termination) of the

power lines, resulting in a high

voltage drop across the lines.
Measure the voltage under load by

placing a load such as a type 1157

brake light bulb between the Ignition

Power pin and Ground pin of the

ECU connector, while the lamp is in

place.
With ignition power to the trailer,

measure the voltage between the

Ignition Power (pin 6) and Ground

(pin 18) of the ECU connector.
Repeat the voltage measurement

with brake lamp power to the trailer,

between the Brake Lamp Power

(pin 12) and the Ground (pin 18) of

the ECU connector.
The operating range of the module

is 8.0-32.0 VDC. Verify that the

voltage drop measurements are no

less than 1.0 VDC from the vehicle

voltage at both the ignition and

brake power inputs.

With a volt/ohm meter, check

the power and ground wiring. Look

for corroded or damaged wires or

connectors.
If repairs are made, rerun the

power-up sequence. Go to

Section A.
If proper loaded and unloaded

voltage is measured at the ECU

connector, and no corrosion or

damage is found on the wiring,

connectors or ECU, replace the

module.

With a volt/ohm meter, check the

power and ground wiring. Look for

corroded or damaged wire or connectors.
If repairs are made, rerun the power‑up

sequence. Go to Section A.

With

ignition

power to the

trailer, measure

the voltage between

the ignition Power pin and the

Ground pin of the ECU connector.

Repeat the voltage measurement with

brake lamp power to the trailer, and between the

Brake Lamp Power pin and the Ground pin of the ECU

connector.

The operating range of the module is

8.0-32.0 VDC. Can you verify that

measurements found are equal

to the vehicle voltage (within

1 VDC) at both the

ignition and brake

power

inputs?

YES

Measure the loaded

voltage across a type

1157 brake light bulb.

Looking into TABS-6 Advanced module

Wire Harness, ECU Connector Measure:

Pin 6 (Ignition Power) to Pin 18 (ground)

and Pin 12 (Brake Light Power) to

Pin 18 (ground).