2nd Gen 4Runner Heater Blower Not Working: The Short List
Four suspects, one afternoon
A dead or misbehaving heater fan on a 2nd gen almost always lands on one of four parts, and the symptom pattern tells you which before you pull a single panel.
Works only on high, dead on low speeds: that's the blower resistor. The resistor pack drops voltage for the lower speeds, and when it burns out, only the direct high-speed path survives. It's the classic failure and a cheap, accessible part.
Dead on every speed: check the fuse first, then put power directly to the blower motor. Motor runs on direct power but not through the truck: suspect the switch or its connector — decades of current can cook the connector before the switch itself dies. Motor silent even on direct power: the motor's done.
Runs but squeals or chirps, especially on cold mornings: the motor bearings are dry and the clock is ticking. Some owners get months more out of a careful cleaning and lube; a replacement motor ends the conversation.
While the dash-side panels are off
Inspect the connectors you can reach for browned or melted plastic — heat damage at connectors mimics every other failure on this list and causes intermittent gremlins that drive owners crazy. And check that the fresh-air intake at the cowl isn't packing thirty falls' worth of leaves against the blower; a choked intake makes a healthy fan feel weak and helps the next motor die young too.
