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Vehicle System Checks

Are there any obvious mechanical issues? 

Are the symptoms exhibited mechanical in nature and not related to any electrical system? Examples of mechanical issues are:

Refer to the service information for the relevant system or the issue may be covered by the list of symptoms in the following:

Is the 12 V battery fully charged and cables are clean and tight? 

It is assumed that the vehicle will be able to start and be driven. But if the vehicle has a battery or charging problem or it is slow cranking or for any other reason the technician feels the customer's concern may be battery related then inspect and verify the battery functions properly. Due to variable electrical charging strategies it is necessary to test battery voltage under different operating conditions to ensure it is working correctly.

Refer to the following service information or technical bulletins for further information:

Are all the fuses related to the fault in an OK condition. 

It is assumed that all fuses are OK, it is expected that technicians can find an open fuse without requiring a DTC repair instruction to direct them to do it. Use service information references below to find power sources and fuse locations that may be related to the customer concern.

Refer to the following service information or technical bulletins for further information:

Are the grounds/earths related to the concern clean, tight, and in the correct location? 

It is assumed that all ground circuits/earths are OK, it is expected that technicians can find an open ground/earth without requiring a DTC repair instruction to direct them to do it. Use service information references below to find ground locations and which ground circuits may be related to the customer concern.

Refer to the following service information or technical bulletins for further information:

Are all connectors/terminals fully seated? 

It is assumed that all connectors or terminals are fully seated, it is expected that technicians can find out if connectors or terminals are fully seated without requiring a DTC repair instruction to direct them to do it. Use service information references below to find connections which may be related to the customer concern.

Refer to the following service information or technical bulletins for further information:

Does the Vehicle power-up correctly? 

When remote key fob is present and driver depresses the brake pedal, all vehicle systems are expected to power up, such as the information display wake up, the radio powers on, the climate control fan is operational, windshield wipers turn on (when operated).

If there is a Power Mode issue investigate the state of electrical terminal clamps (power supply to electric/electronic components within the vehicle) starting with the hardware clamps i.e. relays or electrical drivers. Some clamps are virtual or logical in the form of communication messages between control modules, if there is a fault affecting these then it is likely to be a symptom of another issue and they will need to be addressed in the next section DIAGNOSTIC TROUBLE CODE REPAIR SEQUENCE.

Refer to the following service information or technical bulletins for further information:

Does the scan tool power-up correctly? 

It is assumed that power is available at the OBD diagnostic connector. The scan tool should power-up with the vehicle OFF but may not be able to communicate unless the vehicle is ON. If the scan tool does not power-up check

Refer to the following service information or technical bulletins for further information:

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