Scan Tool Initiated Procedure
WARNING: This page is about a different car, the 2008 GMC Yukon and 2008 Chevrolet Tahoe. However, it is still accessible from the selected car via links, so may be relevant.
- Turn the ignition key to the RUN position. Ensure that the high voltage contactor relays close.
- Observe the HPCM 300 V Circuit voltage in the APM data list on the scan tool.
- If the voltage is less than 194 volts, Jump-Assist will not initiate and the drive motor generator battery must be replaced. Refer to Drive Motor Generator Battery Replacement .
- Connect the 12 volt DC battery charger to the 12 volt vehicle connections ensuring that an electrically secure connection is made. The 12 volt circuit must remain greater than 11.0 volts at the APM during the entire Jump Assist event for a successful Jump Assist to occur.
- Plug in the 12 volt DC battery charger and make certain that it is in the highest continuous CHARGE (Not START) state available. If required, turn the Charger on.
- Connect the scan tool and navigate to the APM Special Functions menu.
- Press the Jump-Assist soft-key on the Scan Tool. The Driver Information Center (DIC) on the instrument panel should now display "JUMP ASSIST READY TURN KEY OFF".
- Shut the scan tool off.
- Turn the ignition key to the OFF position.
- Jump-Assist will initiate and a transfer of energy between the 12 volt DC battery charger and the drive motor generator battery will occur through the APM. The DIC should display "JUMP ASSIST ACTIVE BATTERY CHARGING".
- The scan tool can now be powered up again and the BECM Data Display can then be used to monitor the progression of Jump-Assist. By noting the Hybrid Battery Current, the total amount of time for a successful Jump-Assist can be estimated with the Jump Assist Current vs. Time table:
- The scan tool may also be removed if needed during Jump Assist. Jump Assist will continue until the DIC displays one of the following messages:
- "JUMP ASSIST COMPLETE"
This correlates to a maximum module voltage in the drive motor generator battery of 17.9 volts with less than 0.5 amps of current being applied by the APM for greater than 30 seconds. The vehicle should now start.
- "JUMP ASSIST ABORTED"
This message means that Jump Assist has ceased power conversion early. Before attempting to re-initiate Jump Assist, verify the following conditions:
- "JUMP ASSIST COMPLETE"
IMPORTANT:
Ensure that the 12 volt DC accessory battery is completely charged and tested before attempting to initiate Jump Assist. Refer to Battery Inspection/Test
.
IMPORTANT:
Use a 12 volt DC battery charger rated at greater than 20 amps continuous.
WARNING:
High temperatures may result from failure to make a secure electrical connection. This could result in the potential for personal injury and damage to the vehicle and/or charger due to the extended period of time of operation and high currents involved with Jump-Assist.
- The 12 volt circuit has remained above 11.0 volts.
- DTCs have not been set by the HPCM, APM or BECM.
- The drive motor generator battery is not greater than 358 volts or less than 180 volts.
- The ignition key was not turned to the RUN position during Jump Assist.
Jump Assist Current vs Time
| Hybrid Battery Current (Amps) | Time (Minutes) |
|---|---|
| 0.25 Amps | 228 minutes |
| 0.50 Amps | 114 minutes |
| 0.90 Amps | 63 minutes |
| 1.40 Amps | 41 minutes |
| 1.90 Amps | 30 minutes |
| 2.40 Amps | 24 minutes |
| 2.90 Amps | 20 minutes |