B1452

Fifth bow motors, shorting to ground/open circuit.

Fault Symptom

The fifth bow cannot be operated.

Condition

Open circuit or shorting to ground on pin 13 (K20) or pin 14 (K20).

Diagnostic Procedure





1 Connect an ISAT scan tool and read "5TH BOW MOTOR". Operate the hood by means of the "ROOF" switch. The SAT scan tool should show the state of the motor during operation of the hood. If the SAT scan tool readings are OK, use the scan tool command "DTC DATA" to obtain the value the main potentiometer had when the fault occurred. Try to repeat the fault using this information and check whether the fifth bow can move freely without obstruction. If fifth bow operation is OK, clear the trouble code and check that it is not generated afresh.

2 It one of the two motors is in working order, there is an open circuit in the other motor's wiring. Unplug the detective motor's connector and take a voltage reading across a good ground and pin 1 of the connector and across a good ground and pin 2. Activate the motor at the same time by means of the ISAT scan tool or the "ROOF" switch. A reading of 12v should be obtained on pin 13 (K20) of the control module connector when activated up and on pin 14 (K20) when activated down. If a reading of 12v is obtained on the voltmeter, there is an open circuit between the motor and its connector. Check the wiring between the motor and the connector for continuity. Rectify any faults. If the wiring is OK, change the motor.

3 If a reading of 12v cannot be obtained in the motor's connector, there is an open circuit between it and the emergency hood-raising handle's connector. Check the wiring for continuity.





4 If neither motor is in working order, take a voltage reading across pin 4 in H6-4 and a good ground. Operate the fifth bow motors and check that a reading of 12v is obtained.

5 If the voltage reading obtained is not OK, check the wiring harness between pin 14 (K20) and pin 4 in H6-4 for continuity/shorting to ground.

6 If the voltage reading obtained for H6-4 is OK, inspect the microswitch by the emergency hood-raising handle and check its operation. Take a resistance reading across pins 4 and 6 and also across pins 4 and 5.

If in proper working order, a reading of less than 1 ohm should be obtained.





7 Also check the wiring harness between the two motors and pin 13 (K20) of the TSAS control module and between the two motors and H6-4 for continuity/shorting to ground.