2010 Cadillac Truck Escalade RWD V8-6.2L Page 1560
* Identify how to disable high voltage.
* Identify how to test for the presence of high voltage.
* Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must
be followed.
Failure to follow the procedures exactly as written may result in serious injury or death.
1. Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling ().
2. Disconnect the air conditioning control module terminal X4 B+ (300 V) and terminal X5 ground (300 V).
3. Test for infinite resistance between the terminals listed below and ground;
* X4 B+ (300 V) cable
* X5 ground (300 V) cable
瀚慖f less than the specified value, replace the air conditioning control module assembly.
4. Test for greater than 50k ohm between the B+ (300 V) terminals X4 and ground (300 V) X5.
瀚慖f less than the specified range, test the circuits for a short between the circuits. If the circuits test normal, replace the air conditioning
control module assembly.
5. Connect the EL-48458 at the drive motor generator power inverter module. Refer to the EL-48458 installation procedure located in High
Voltage System Diagnosis (EL-48458) ().
Note: Install a manual disconnect lever with a verified good fuse or a new manual disconnect lever.
6. Install the manual disconnect lever.
7. Connect the 12 V battery.
8. Ignition ON, attempt to precharge the high voltage system by moving the high voltage contactor relay switch on the tester to the closed
position. Verify that the hi-voltage greater than 60 V LED does not illuminate.
瀚慖f the LED illuminates, replace the drive motor generator power inverter module.
Note: The following tests require wearing personal protection equipment (PPE) gloves.
9. Ignition OFF, remove the EL-48458. Refer to the removal procedure located in High Voltage System Diagnosis (EL-48458) ().
10. Ignition OFF, disconnect the X1 B+ (300 V) and X2 ground (300 V) cables from the drive motor generator battery.
11. Test for infinite resistance between the terminals listed below and ground
* X1 B+ (300 V) cable
* X2 ground (300 V) cable
瀚慖f less than the specified value, replace the high voltage cables.
12. Ignition ON, command the negative and positive contactors and the current limit relay ON and OFF with a scan tool. Listen for the contactors
and relay to turn ON and OFF.
瀚慖f the negative contactor, positive contactor or the current limit relay does not turn ON and OFF, refer to High Voltage Contactor/Relay
Malfunction ().
13. Ignition OFF, visually inspect and test the drive motor generator battery internal high voltage DC cables and connections for a short to
ground or an open/high resistance condition.
瀚慖f a short to ground or an open/high resistance condition is found on the high voltage cables or connection points, replace the drive motor
generator battery cable.
14. If all the circuit tests normal, replace the drive motor generator battery assembly.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the repair.
* Drive Motor Battery Negative Relay Cable Replacement ()
* Drive Motor Battery Positive Relay Cable Replacement ()
* Drive Motor Battery Positive and Negative Cable Replacement ()
* Drive Motor Battery 300-Volt Positive and Negative Cable Replacement ()
* Control Module References (See: Testing and Inspection/Programming and Relearning) for drive motor generator battery control module,
