NTI PRO APPS ABS EXAM QUESTIONS
AND ANSWERS
What can cause the ABS warning light to turn on? - Answer-Pump motor on/off, speed
sensor, voltage, low fluid, accumulator pressure, diff pressure switch, modulator
solenoids, and relay
What could having aftermarket transmitting equipment too close to the ABS cause? -
Answer-Intermittent ABS light being turned on and off
What's the different in Delco VI and all others? How would you tell it's bad in a scan
tool? - Answer-Delco VI uses a motor pack and 3 pistons to reduce or add pressure to
the system. In a snapshot you would observe motor amp draw and direction
If the ABS light comes in during start up for a few seconds and turns off what's that
called? If it turns on when you move why could be the problem? - Answer-Self test while
at rest. WSS, the module can't see wheel speed until the car moves.
4 ways to test a WSS - Answer-Scan tool, volt meter, resistance, Visual, air gap
Why do we need to be careful when servicing a an accumulator? - Answer-Its under
high pressure
Should all tire sizes be the same? - Answer-Yes
What is a DRAC module? - Answer-Digital radio adapter controller. Converts AC analog
to DC Digital
What kind of voltage is produced by a wheel speed sensor? - Answer-Most sensors
produce AC analog signals
How does the computer know if a speed sensor has an open circuit? - Answer-
Reference voltage sent through it during self diagnostics while the vehicle is at rest.
What can a scan tool be used for on an ABS system? - Answer-Pull Codes, View data
stream, bleed system, actuate solenoids and relays
What could a damaged tone ring do to an output signal? - Answer-Could cause it to be
erratic
Can a chirping sounds during braking indicate total lock of the tire? - Answer-No
Where may you find a speed sensor tone ring? - Answer-CV joint, inside brake drum, in
differential, or on the trans tail shaft
AND ANSWERS
What can cause the ABS warning light to turn on? - Answer-Pump motor on/off, speed
sensor, voltage, low fluid, accumulator pressure, diff pressure switch, modulator
solenoids, and relay
What could having aftermarket transmitting equipment too close to the ABS cause? -
Answer-Intermittent ABS light being turned on and off
What's the different in Delco VI and all others? How would you tell it's bad in a scan
tool? - Answer-Delco VI uses a motor pack and 3 pistons to reduce or add pressure to
the system. In a snapshot you would observe motor amp draw and direction
If the ABS light comes in during start up for a few seconds and turns off what's that
called? If it turns on when you move why could be the problem? - Answer-Self test while
at rest. WSS, the module can't see wheel speed until the car moves.
4 ways to test a WSS - Answer-Scan tool, volt meter, resistance, Visual, air gap
Why do we need to be careful when servicing a an accumulator? - Answer-Its under
high pressure
Should all tire sizes be the same? - Answer-Yes
What is a DRAC module? - Answer-Digital radio adapter controller. Converts AC analog
to DC Digital
What kind of voltage is produced by a wheel speed sensor? - Answer-Most sensors
produce AC analog signals
How does the computer know if a speed sensor has an open circuit? - Answer-
Reference voltage sent through it during self diagnostics while the vehicle is at rest.
What can a scan tool be used for on an ABS system? - Answer-Pull Codes, View data
stream, bleed system, actuate solenoids and relays
What could a damaged tone ring do to an output signal? - Answer-Could cause it to be
erratic
Can a chirping sounds during braking indicate total lock of the tire? - Answer-No
Where may you find a speed sensor tone ring? - Answer-CV joint, inside brake drum, in
differential, or on the trans tail shaft
