Conditions for Setting the DTC
* The amplifier receives a serial data message that the engine is running.
* The discrete engine speed signal to the amplifier indicates the engine speed is less than 300 RPM or greater than 9000 RPM.
Action Taken When the DTC Sets
The active noise cancellation system is disabled.
Conditions for Clearing the DTC
* A current DTC clears when a valid engine speed signal between 300-9000 RPM is received.
* A history DTC clears when the ignition cycle counter reaches the reset threshold without a repeat of the malfunction.
Reference Information
Schematic Reference
Active Noise Cancellation Schematics (See: Accessories and Optional Equipment/Diagrams/Electrical Diagrams/Active Noise Cancellation
Schematics)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
Active Noise Cancellation Description and Operation (See: Accessories and Optional Equipment/Description and Operation/Active Noise
Cancellation Description and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic
Procedures/Connector Repairs/Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General
Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring
Repairs/Wiring Repairs)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Circuit/System Testing
Note: Diagnose any engine control module DTCs before performing this diagnostic.
1. Ignition OFF, disconnect the X4 harness connector at the amplifier.
2. Test for less than 10 ohm between the engine speed low signal circuit terminal 8 and ground.
锟斤拷 If not within the specified range, test the circuit for an open/high resistance, or short to voltage. If the circuit tests normal replace the ECM.
3. Engine running at 600 RPM, test for 275-325 Hz AC between the engine speed high signal circuit terminal 7 and ground.
锟斤拷 If not within the specified range, test the circuit for a short to ground, open/high resistance, or short to voltage. If the circuit tests normal
replace the ECM.
4. If all circuits test normal, replace the amplifier.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning)for amplifier or ECM replacement, setup, and programming
MP 3010-NP0 - Transfer Case
DTC B0770
Diagnostic Instructions
