Electrical

Electrical System Diagnostics & Repair — Keep Your Vehicle Powered and Reliable

Modern vehicles rely heavily on their electrical systems. From starting the engine to powering sensors, computers, lights, and accessories, even a small electrical issue can cause major problems. At Johnny’s Auto Repair & Services, we provide reliable mobile electrical diagnostics and repair for both American and European vehicles, getting to the root of electrical faults quickly and professionally.

What Your Vehicle’s Electrical System Does

Your electrical system powers and controls nearly every part of your vehicle, including:

• Starting & charging system

• Battery, alternator, and starter

• Lights and interior electronics

• Sensors & control modules

• Power windows, locks, and seats

• Ignition system

• Fuel system electronics

• Safety systems (ABS, airbags, traction control)

• Climate control & HVAC electronics

• Dashboard components & instrument cluster

When something goes wrong, you need accurate diagnostics — not guesswork.

Electrical Services We Provide

We diagnose and repair a wide range of electrical issues, including:

Battery, Alternator & Starter Diagnostics

No-start issues, dim lights, dead battery, charging failures, voltage drops.

Electrical Shorts & Parasitic Draw Testing

Fixing battery drains, blown fuses, and wiring faults.

Fuse & Relay Inspection & Replacement

Identifying failed fuses, relays, and power distribution issues.

Sensor & Module Diagnostics

O2 sensors, MAF/MAP, ABS sensors, ignition coils, wheel speed sensors.

Lighting & Accessory Electrical Repairs

Headlights, brake lights, interior lights, power windows, door locks.

HVAC Electrical Problems (Non-A/C)

Blower motors, resistors, switches, control panel malfunctions.

Communication & CAN-Bus Issues

Diagnosing module communication errors, network faults, and signal interruptions.

European Electrical System Diagnostics

Advanced systems on BMW, Audi, Mercedes, VW, Volvo, etc.

We find the root cause — not just the symptoms.

Electrical Services We Do NOT Provide

To keep customers informed and prevent confusion:

We DO NOT service or diagnose:

• Refrigerant-based A/C cooling issues

• Evaporators, compressors, condensers

• Airbag/SRS module reprogramming

• Full re-wiring of entire vehicles

• Dealer-only programming that requires proprietary tools

(We can handle blower motors, HVAC controls, A/C electrical issues — just not refrigerant/cooling performance diagnostics.)

Signs You Have an Electrical Problem

If you notice any of the following, your electrical system may need attention:

• Battery keeps dying

• Lights flicker or are dim

• Car won’t start or starts inconsistently

• Warning lights appear without symptoms

• Electrical accessories stop working

• Burning or electrical smell

• Random stalling or power loss

• Fuses repeatedly blowing

• Clicking when turning the key

• Modules losing communication

• Windows/locks/key fob not working

Electrical issues can get worse fast — early diagnosis saves money.

Our Electrical Diagnostic Process

We perform a complete step-by-step diagnosis to identify the exact cause:

1) System Scan

Read codes and data from every module (engine, ABS, body control, etc.).

2) Circuit Testing

Voltage drop testing, continuity checks, resistance testing.

3) Component Verification

Testing sensors, relays, fuses, switches, and wiring.

4) Battery & Charging Test

Measure battery health, alternator output, and starter draw.

5) Root Cause Confirmation

We verify the exact failure so no unnecessary parts are replaced.

6) Clear Explanation

You get a full breakdown of what’s wrong, why it's failing, and how to fix it.

No guessing. No parts cannon. Real answers.

American/Japanese vs. European Electrical Systems

American/Japanese Vehicles

• Straightforward wiring

• Good parts availability

• Less complicated modules

• Easy access to electrical components

European Vehicles

• More complex wiring networks

• Multiple computers & communication systems

• Voltage-sensitive modules

• Often require precise diagnostics

We handle both correctly and safely.

Mobile Electrical Repair — Fast, Convenient, and Reliable

As a mobile mechanic, we bring professional electrical diagnostics to your home or workplace, saving you from towing fees or long shop wait times.

You get:

• Accurate diagnostics

• High-quality electrical repairs

• Clear explanations

• Upfront pricing

• Experienced service for American/Japanese & European vehicles

• No hidden fees

• Warranty on most repairs

Electrical problems can be frustrating — we make them easy to understand and fix.