Toyota & Lexus Electrical Service

• Battery testing, service, and replacement (12V systems)

• Hybrid high-voltage battery assessment and service

• Alternator testing and replacement

• Starter motor diagnosis and replacement

• Charging system diagnosis

• Wiring harness inspection and repair

• Short circuit and open circuit diagnosis

• Fuse, relay, and junction block service

• Body Control Module (BCM) diagnosis

• Engine Control Module (ECM) diagnosis and programming

• CAN bus network communication fault diagnosis

• Power window, lock, and mirror system repair

• Lighting system diagnosis and repair (including LED and adaptive headlights on Lexus models)

• Accessory and convenience feature diagnosis

• ​Hybrid system electrical diagnosis (inverter, converter, hybrid ECU)

Electrical faults are among the most challenging diagnostic problems in modern vehicles — and they're especially complex on Toyota and Lexus platforms, which use a multi-network CAN bus architecture where dozens of control modules communicate with each other constantly. A fault in one module can generate warning lights and symptoms in a completely different part of the vehicle, leading to misdiagnosis if the technician doesn't understand how these systems are interconnected.

Toyota and Lexus use proprietary diagnostic protocols that generic scan tools and code readers can only partially access. Full system scans — reading codes from every module on the network simultaneously — require Toyota-specific diagnostic software. This is how we approach every electrical concern: start with a complete system scan, understand the full picture, then diagnose from there.

Toyota and Lexus hybrid vehicles add a second, high-voltage electrical system to the standard 12V vehicle electrical system. The high-voltage system — operating at 200–650V depending on the model — powers the electric drive motors, the regenerative braking system, and (in plug-in models) the charging system. It is a completely separate system from the 12-volt battery that powers accessories and starts the vehicle.

High-voltage system work requires specific safety training and equipment. Our technicians are trained in hybrid high-voltage system safety and have the tools to properly diagnose hybrid electrical faults — including hybrid battery capacity testing, inverter diagnosis, and hybrid ECU fault analysis.

The 12V auxiliary battery in hybrid vehicles also has a different failure pattern than in conventional vehicles. Because the hybrid system can mask a weakening 12V battery (the hybrid system compensates), hybrid owners sometimes don't notice a failing auxiliary battery until it's completely dead. We test both systems as part of our hybrid electrical service.

• Battery warning light, charge system light, or hybrid system warning illuminated

• Difficulty starting (slow crank, clicking, or no response)

• Lights dimming or flickering, especially under electrical load

• Accessories (windows, locks, mirrors, infotainment) behaving erratically or failing

• Blown fuses that keep coming back

• Burning smell or visible signs of heat damage near wiring

• Multiple warning lights on at the same time (often indicates a module communication fault)

• Hybrid "ready" light not appearing, or hybrid warning triangle illuminated

• Intermittent faults — things that work sometimes and not others

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Intermittent electrical faults are particularly important to mention when you drop your vehicle off. They're often harder to reproduce in the shop, so the more detail you can provide about when and how the issue occurs, the more efficiently we can locate it.

Electrical diagnosis is where the gap between a Toyota and Lexus specialist and a general repair shop is widest. These vehicles use complex, interconnected systems with proprietary protocols — the right tools, the right software, and the right experience all matter. We've been working on Toyota and Lexus electrical systems through every generation of their technology, from the early OBD systems to today's multi-network hybrid architectures.

We don't guess with electrical work. We diagnose systematically, explain what we find, and repair it correctly.