Finding and fixing an electrical issue in your car can be incredibly frustrating. You know something is wrong, but you have no idea where to start looking or what could be causing the problem. This article will walk you through some common electrical gremlins, how to diagnose them, and how to finally banish that issue for good.
Identifying the Electrical Issue
The first step is identifying exactly what the problem is. Here are some common electrical gremlins and what to look for:
Strange or Erratic Dashboard Lights
If I notice dashboard lights flickering, dimming, or brightening randomly, it likely points to a wiring or electrical connection issue. Flickering lights when hitting bumps or turning points to a short circuit somewhere.
I need to pay attention to any other electrical components like the radio or HVAC controls acting up at the same time. That can help identify the problem area.
Power Windows or Locks Misbehaving
When my power windows and door locks start acting erratically, not working smoothly or at all, it's likely a bad switch, motor, regulator or electrical short in the wiring.
Problems when the car hits bumps indicates a wiring harness issue. If the windows or locks only act up intermittently, I may have a loose connection or worn out switch.
Electrical Components Turning Off Randomly
If the headlights, interior lights, or other electrical components seem to turn off at random for no reason, it points to an electrical supply issue.
The battery, alternator, or wiring supplying power to those components should be inspected for corrosion, bad connections, or general wear and tear.
No Start Condition
A no start can be caused by many issues, but electrical problems like a bad starter solenoid, ignition switch, or battery connection should be ruled out first.
Listen for click or turnover attempt when the key is turned. No click indicates an ignition or starter relay problem. A click but no turnover points to a starter solenoid or battery issue.
Diagnosing the Electrical Fault
Once I've identified the misbehaving electrical component, here are some tips on diagnosing exactly what's wrong:
Inspect Wiring and Connections
I'll carefully inspect the related wiring harnesses and electrical connectors first. Check for any corroded or loose connections, damaged insulation, pinched or bare wires. I pay special attention to wires near hot components or moving parts as engine heat and vibration commonly cause issues.
Check Electrical Components and Switches
I test any related electrical components like motors, regulators, switches and sensors with a multimeter. Check for continuity, resistance specs, and input/output voltages to determine if internal components have failed.
Utilize Vehicle Diagnostic Systems
I plug an OBD-II scanner tool into the vehicle computer port and check for any diagnostic trouble codes (DTCs) stored related to the electrical fault. The make, model, year specifics of the code can help identify the malfunctioning part.
Electrical Testing and Diagnosis
For complex issues, I may need more advanced electrical diagnostic testing. Circuit and voltage drop testing can find electrical shorts, opens and high resistance problems in wiring harnesses. An amp clamp can measure current draw on a circuit to find excessive loads.
Repairing the Electrical Gremlin
Once I've diagnosed the specific electrical problem, it's time to get it fixed:
Replace Damaged Wiring and Connectors
For wiring harness or connection issues, I repair or replace any damaged wires, connectors, or terminals. Soldering wires and protecting with heat shrink tubing creates solid, lasting repairs. I avoid just taping over cuts as it often leads to future issues.
Swap Out Faulty Electrical Components
If I diagnosed a bad motor, switch, relay, etc., I remove and replace it with a new part. For easier repairs, I often replace whole assemblies like window regulators or lock actuators rather than just the internal motor.
Clean Corroded Battery and Starter Cables
Corroded, oxidized battery and starter cable connections can cause a host of electrical headaches. I carefully clean the cable ends and battery terminals to remove all dirt and corrosion.
Consider Electrical Repair Shops for Complex Issues
For certain electrical faults like interior wiring shorts, PCM/ECU failures, or general "ghosts", I may need to seek professional help from an auto electrical repair shop. They have the expertise and equipment to handle more advanced diagnostics and repairs.
Preventing Future Electrical Gremlins
To help prevent electrical issues from popping up again, here are some important maintenance tips:
Inspect wiring harnesses near hot or moving components frequently for damage. Replace cracked insulation immediately.
Spray electrical connections with dielectric grease or corrosion block to protect from moisture and oxidation.
Maintain battery andstarter connections to avoid corrosion.
Replace aging switches, motors and relays. Electrical components wear out over time.
Update vehicle grounds straps if corroded. They are vital for proper electrical operation.
Consider marine grade or sealed wiring components if driving in wet conditions frequently.
By identifying the electrical fault, properly diagnosing the issue, repairing the problem fully, and practicing preventive maintenance, I can banish those annoying electrical gremlins from my vehicle once and for all!