Diagnosing Engine Issues
Purpose: This article provides guidance for identifying and responding to engine fail-to-start conditions, especially when accompanied by specific Diagnostic Trouble Codes (DTCs). These codes may appear during hybrid battery replacement or immediately afterward and may indicate issues unrelated to the battery itself…
Understanding the Red Triangle Master Warning Light on Hybrid Vehicles
Purpose: This article explains what the red triangle master warning light means in hybrid vehicles, why it doesn’t automatically indicate hybrid battery failure, and how to troubleshoot it. 🚨 What is the Red Triangle Warning Light? The red triangle warning light on your hybrid dashboard is known as the Master W…
What Is Limp Mode in a Hybrid Vehicle? Causes, Symptoms & How to Fix It
If you’ve ever been driving your hybrid and suddenly noticed poor acceleration, warning lights on the dash, or an engine that won’t rev past a certain point, you may have experienced limp mode — a safety feature that’s as frustrating as it is misunderstood. In this article, we’ll explain: * What limp mode is a…
Understanding U-Codes in Hybrid Vehicles: Common Causes and How to Diagnose
In the world of automotive diagnostics, U-codes are reserved for communication errors between control modules . In hybrid vehicles, U-codes can play a major role in diagnosing issues — especially when they affect systems like the hybrid control ECU, battery ECU, or brake ECU. This guide will help you: * Under…
What Does Code P0AA6 Mean on a Hybrid? Ground Fault Diagnosis Explained
Hybrid vehicles are engineered with high-voltage systems that require strict insulation between the battery pack and the vehicle chassis. When this insulation breaks down, the system will often trigger a P0AA6 diagnostic trouble code. This article will help you understand: * What code P0AA6 means * Common cau…
Understanding Hybrid Brake Trouble Codes C1241, C1310 and C1259: What They Mean & How to Fix Them
If you own a Toyota or Lexus hybrid and see C1241, C1310 or C1259 stored in your system, you're not alone. These codes often appear together and can confuse even seasoned techs because they involve both the brake system and hybrid control system . In this article, we’ll break down: * What each code means …
Pending vs. Current vs. Permanent Trouble Codes: What’s the Difference?
Understanding How Diagnostic Trouble Codes Work in Hybrid and Gas Vehicles When you scan your vehicle using a code reader or scan tool, you might see terms like pending , current , or permanent next to a trouble code. But what do these labels mean? Does a pending code mean something's wrong? Can you clear a pe…
What to Do If Your Prius Won’t Start (But the Lights Turn On)
A Complete Diagnostic Checklist for Prius Owners You get in your Toyota Prius, press the power button… and nothing. The lights come on, but the car doesn’t go into READY mode. You’re not alone — this is a common hybrid-specific issue , and it doesn’t always mean your hybrid battery is dead. In this guide, we’ll …
Hybrid Battery & System Trouble Codes Explained: What They Mean and What to Do
If you've scanned your hybrid vehicle and discovered one or more diagnostic trouble codes (DTCs) , you're probably wondering: * Is my hybrid battery failing ? * Is this a serious issue or just something minor? * Do I need to replace the battery , a sensor, or something else entirely? This article breaks do…
Hybrid Battery vs. 12V Battery Failure: How to Tell the Difference
Hybrid vehicles rely on two key battery systems: a high-voltage hybrid battery (HV battery) and a traditional 12-volt auxiliary battery . When your hybrid won’t start, behaves oddly, or displays warning lights, it can be tough to know which one is to blame. Knowing how to tell the difference can save time, money, …
