Computer Control

Question 1

A - a greenish corrosion on terminals results in high resistance in the circuit.
B - loose retaining lock tabs on a terminal can cause high resistance in connector terminals.

Answer 1

both correct

Question 2

A - when replacing the PCM, the new PCM may have to be reprogrammed in order for it to operate.
B - some drivability problems can be fixed by reprogramming the PCM.

Answer 2

both correct

Question 3

A - the best way to clear DTCs is to remove the battery negative terminal for five seconds.
B - the monitor for the repaired system should be performed before the vehicle is returned to the customer.

Answer 3

A - incorrect. Use a scan tool.

B - correct.

Question 4

A - a DTC tells you which component is malfunctioning.

B - if a fault exists that affects emissions, then the MIL will be illuminated.

Answer 4

A - incorrect.

B - correct.

Question 5

A vehicle with a MIL is being diagnosed. The DTC stored is P0300 (random / multiple cylinder misfire detected).
A - this is a one-trip failure, because catalyst damage can occur.
B - the MIL will flash on this type of code.

Answer 5

both correct

Question 6

A scan test on a late model fuel injection engine reveals a bank #1 long term fuel trim value of -19, and a bank #2 long term fuel trim value of -18 with the engine idling.
A - these readings could be caused by a defective fuel pressure regulator.
B - a restricted fuel return line could cause these readings.

Answer 6

both correct

Question 7

A MAF load calculating type port fuel injected engine runs fine at idle, but hesitates under acceleration. No DTCs are stored.
A - check for a restricted MAF inlet screen.
B - a bad spot in the TPS signal could be the cause.

Answer 7

both correct

Question 8

A vehicle has a DTC for an open vehicle speed sensor circuit. Which of the following systems would most likely be affected?
A - air conditioning
B - manual transmission shift points
C - traction control system
D - cruise control system

Answer 8

d - most likely

Question 9

A DTC for an IAT sensor may be set by any of the following conditions except:
A - an open in the voltage reference wire.
B - operating the vehicle in extremely cold climates.
C - a short in the voltage reference wire.
D - an out of range sensor input.

Answer 9

b - cold climates will not cause a DTC.