Technical information

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Technician Guidelines for Antilock Braking Systems
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Whenever an additional grounding point is to be established
on the vehicle, consult the vehicle manufacturer to ensure that
the planned alteration does not result in an inadequate ground
path for other components on the vehicle. This is especially
important when establishing a grounding point between chassis
and body.
c. Wiring Damage Caused During Repair
Mechanical damage to wiring must be avoided during
vehicle repair. Insulation cuts and “pinch points” are common
problems which may cause failure.
Conductor insulation should not be pierced while
troubleshooting electrical problems. Piercing of the protective
covering results in corrosion which can cause circuit failure. If
piercing of the insulation is unavoidable, suitable insulation to
avoid water entry must be used at the point where the
conductor was pierced.
d. Vehicle Repairs—Special Care
Many times vehicle repairs include welding operations. All
welding on a vehicle should be done using methods and
techniques which are acceptable to the OEM in order to avoid
damage to the electrical and electronic system of the vehicle.
This damage normally occurs due to unwanted circuit paths or
to voltage spikes created in the electrical and electronic systems
which cause component failure.
CAUTION: When welding on an ABS-equipped vehicle,
disconnect power and ground leads from the ECU to avoid
unintended grounding through the ECU which will damage
electronic components. Other damage may occur to vehicle
systems as a result of heat generated during the welding
process. Special care must be taken to ensure that heat buildup
does not melt conductors and other susceptible electrical
components.
e. Miscellaneous
The use of “star washers” in the electrical path is
discouraged. Often, an open circuit or high resistance results
when the “points” of the washer are exposed to salt spray and
other corrosive materials. If the use of star washers cannot be
avoided, a suitable material should be applied to the
connections to ensure as much protection from corrosion as
possible.