2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 1136

2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 1136

- Hybrid Battery Current Sensor Circuit High Voltage

DTC P1A07

- Battery Energy Control Module 5-Volt Reference Circuit

Diagnostic Fault Information

Circuit/System Description

The hybrid battery current sensor is mounted inside the drive motor generator battery assembly. The positive high voltage cable that goes to the

positive contactor relay passes through the current sensor. The current sensor detects the amperage that flows in and out of the hybrid batteries. The

drive motor generator battery control module supplies and monitors a 5 V reference signal to the current sensor. The current sensor returns a signal

between 0 and 5 V to the drive motor generator battery control module. The current sensor signal is in proportion to the amperage going in and out

of the drive motor generator battery. A signal voltage of the current sensor greater than 2.5 V indicates that the drive motor generator battery is

being discharged and a signal voltage less than 2.5 V indicates charging. The hybrid battery current sensor has 3 measurement ranges in order to

maintain accuracy. The ranges are low, medium and high. The measurement ranges of the current sensor have some overlap with each other. The

low range measures from -22 to +22 A. The medium range measures from -52 to +52 A. The high range measures from -250 to +250 A.

Conditions for Running the DTC

* The ignition is ON.

* The 12 V battery is 9-18 V.

Conditions for Setting the DTC

P0AC0

One of the following conditions exists:

* The drive motor generator battery control module detects greater than 5 A on the current sensor after a successful high voltage system power

down and after the contactors have opened.

* The drive motor generator battery control module detects an increase in total pack voltage greater than 10 V and the current sensor measures

less than a 0.5 A increase.

* The drive motor generator battery control module detects less than 20 A on the high range sensor and the difference between the high range

current measurement and the medium range current measurement is greater than 20 A for 3 seconds.

* The drive motor generator battery control module detects less than 20 A on the high range sensor and the difference between the high range

current measurement and the low range current measurement is greater than 4 A for 3 seconds.

P0AC1

The drive motor generator battery control module detects that the current sensor high range is greater than +200 A and the current sensor medium

range is greater than +52 A and the current sensor low range is greater than +22 A for 3 seconds.

P0AC2

The drive motor generator battery control module detects that the current sensor high range is less than -200 A and the current sensor medium range

is less than -52 A and the current sensor low range is greater than -22 A for 3 seconds.

P1A07

The drive motor generator battery control module detects less than 4.8 V or greater than 5.2 V on the 5 V reference circuit.

Action Taken When the DTC Sets

* DTC P0AC0, P0AC1, P0AC2, and P1A07 are type A DTCs.

* The driver information center (DIC) displays the SERVICE HYBRID SYSTEM message.

* State of charge goes to invalid.

* The drive motor generator battery control module sends a message to the hybrid powertrain control module requesting that the hybrid battery

power limit be set to 3 kilowatts, resulting in minimal hybrid function.

Conditions for Clearing the DTC

DTC P0AC0, P0AC1, P0AC2, and P1A07 are type A DTCs.