Rodent Damage to Car Wiring: Signs, Repair & Prevention
Rodent damage is one of the most common electrical problems we see on the Peninsula — rats and mice nest in warm engine bays and chew wiring, hoses and insulation. Most cases start with sudden warning lights after the car sat overnight. A proper repair traces every damaged circuit, not just the first broken wire.
Call (650) 588-9199Labor Time
From under an hour for a single splice to most of a day for a main engine harness
Typical Cost
Quoted after inspection — depends on how many circuits were chewed and where
Serving
San Bruno, South San Francisco, Daly City, Colma, Pacifica, Millbrae, Burlingame
Warranty
1-year workmanship warranty on the repair
Common Symptoms
If you experience these symptoms, your All Makes All Models may need rodent damage repair:
Why This Happens
Understanding the root cause helps prevent future issues:
Our Repair Process
How we handle rodent damage repair at Express Auto in San Bruno:
Inspection: engine bay, under the intake where reachable, air box and cabin air filter housing
Scan all modules and record every fault code, not just the check engine light
Trace each affected circuit end to end — rodents rarely chew just one wire
Repair: soldered, heat-shrunk splices for small damage; new pigtails or harness sections where insulation is chewed along a run
Remove nests and droppings, replace the cabin air filter and any chewed vacuum lines or insulation
Clear codes, verify every system (including ADAS cameras and sensors) and road test
Photos of the damage and repair for your records or your insurer
Parts & Warranty
Parts Used
wiring
Automotive-grade wire, sealed connectors and adhesive-lined heat-shrink
pigtails
OEM or OE-equivalent sensor pigtails and connectors
harness
OEM harness sections when damage is extensive
Service Details
Labor Time
From under an hour for a single splice to most of a day for a main engine harness
Typical Cost
Quoted after inspection — depends on how many circuits were chewed and where
Warranty
1-year workmanship warranty on the repair
Frequently Asked Questions
Does insurance cover rodent damage to my car?
Often yes — rodent damage usually falls under the comprehensive portion of an auto policy, subject to your deductible. Coverage varies, so check with your insurer. We provide a written estimate and photos, which is what most insurers ask for.
How do I keep rats out of my car?
Park in a closed garage when possible, remove food and pet food from the garage, clear ivy and debris near where you park, drive the car regularly, and open the hood occasionally if it sits for days. Some owners use deterrent sprays or ultrasonic devices with mixed results. After a repair, we check the cabin air filter housing and air box for new nesting at your next visit.
Will the problem come back after the repair?
The repair itself is permanent, but rodents can return if the car is parked in the same conditions. Most repeat cases we see are cars that sit outside for days near open space.
Can rodent damage cause a car not to start?
Yes. Chewed crankshaft or camshaft position sensor wires, injector wiring or a main engine harness can prevent starting. A chewed wire can also short and drain the battery.
Need this All Makes repair?
Book online in 2 minutes — no deposit. Honest estimate before any work — we service All Makes All Models and other makes.