2020 Toyota 4Runner: Soy wiring harness-rodent chewing
Common wear/failure (not a recall)
Symptoms
Owners of the 2020 4Runner report: soy wiring harness-rodent chewing. CarComplaints.com lists 1 owner complaints, average mileage 6,000 miles.
NHTSA has 1 owner complaints for the 2020 4Runner in this area. Examples:
- NHTSA complaint ODI #11760224 (filed 08/28/2026): “The door actuator have been replaced a minimum of eight times. huge safety risk involved since we never know if the vehicle is going to lock. toyota continues to replace them but not addressing the underlying issue. not sure if this is all related but the blo…”
Likely causes
Sources do not establish a single root cause; diagnosis is needed. Owner-reported fixes are listed below.
Fix, in plain English
Most common owner-reported solutions on CarComplaints.com: replacement of harness (1 reports). Check for open recalls and extended warranty coverage with a dealer before paying out of pocket.
DIY difficulty: Moderate
Finding and splicing chewed wiring is doable with a multimeter and patience but can be time-consuming; harness replacement is pro work. (Our assessment.)
Cost
CarComplaints.com owners report a typical repair cost of about $3,220 (owner-reported average, not a quote).
Typical parts (search links, no affiliate codes)
AutoZone · O'Reilly · Advance · RockAuto
Sources
- CarComplaints.com: Soy wiring harness-rodent chewing (2020 4Runner)
- NHTSA complaints API, 2020 4Runner
Page last updated .