Symptoms - Hybrid Energy Storage. GMC Truck Yukon XL Denali 2008

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2008 🢒 Yukon XL Denali 🢒 Body Systems 🢒 Adjustable Pedals 🢒 Symptoms - Hybrid Energy Storage

Important: The following steps must be completed before using the symptom tables.

Perform the Diagnostic System Check - Vehicle before using the symptom tables in order to verify that all of the following are true:

•	There are no DTCs set.

•	The control modules can communicate via the serial data link.

Review the system operation in order to familiarize yourself with the system functions.

Refer to the following procedures:

•	Drive Motor Generator Battery Venting and Cooling Description.

•	Drive Motor Battery High Voltage Contactor Relay Operation.

•	Inspect for aftermarket devices which could affect the operation of the HVAC System. Refer to Checking Aftermarket Accessories.

•	Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

•	Blocked or restricted hydrogen battery vent tube may cause drive motor battery odor.

•	Inspect the air distribution system for blocked or damaged air inlet or outlet ducts, which cause reduced air flow.

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections.

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

•	Drive Motor Generator Battery Odor

•	Drive Motor Generator Battery Noise