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P1A27




DTC P1A26 or P1A27

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

DTC Descriptors
DTC P1A26
- Hybrid Battery 1 Voltage Low

DTC P1A27
- Hybrid Battery 1 Voltage Very Low

Circuit/System Description

The battery energy control module (BECM) monitors the hybrid battery 1 voltage to detect if the minimum voltage is less than the calibration value.

Conditions for Running the DTC

The engine is running.

Conditions for Setting the DTC

P1A26

Minimum module voltage is less than calibration value for 3 seconds.

P1A27

Minimum module voltage is less than calibration value for 40 ms.

Action Taken When the DTC Sets

The hybrid system is disabled.

Conditions for Clearing the DTC

P1A26, P1A27

System voltage 11-18 volts.

Reference Information
Schematic Reference

Hybrid Controls Schematics (Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Generator Battery Carrier Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification
P1A26, P1A27

1. If other DTCs are set diagnose those first.
2. These DTCs are for information only. The DTCs can set in cold weather. Clear the DTC, no diagnostic or removal/replacement procedures are required.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.