Lexus GX 470: VSC TRAC and VSC OFF lights on, with or without a check engine light

Checks, in order

1. Read every code
   Scan the engine first. P0420/P0430 and EVAP codes (gas cap, filler neck O-ring, purge valve) are the usual triggers. Fix the engine code and the VSC lights clear with it; C1201 simply means an engine fault is present.
   easy $ · under about $50
2. Check charging voltage
   Below about 13.5 V running or 12.4 V at rest, the battery or alternator is the problem, and low voltage can set sensor codes all over the truck.
   easy $ · under about $50
3. Zero point calibration
   After a battery disconnect, alignment or suspension work, the yaw rate and deceleration sensor can need a zero point calibration. It is done with Techstream or the factory jumper procedure in the service manual; do it on level ground.
   medium $ · under about $50
4. Steering angle and wiring
   C1335 and similar codes point to the steering angle sensor or its harness under the column. Check connectors before replacing sensors.
   medium $$ · about $50 to $500

Applies to: Lexus GX 470, 2003 to 2009, with the 4.7L 2UZ-FE V8 (timing belt) and the A750F 5-speed automatic. Every US GX 470 has rear air suspension; KDSS was optional from 2004. It shares its chassis with the 4th gen 4Runner and 120 Series Prado, so many 4Runner parts and procedures apply.

Tools and parts for these checks

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Other body & electrical problems on the Lexus GX 470

• Dashboard cracked, sticky or shiny and soft in the heat
• Rear swing-out door will not open from outside or inside, or will not latch

More Lexus GX 470 problems

• Rear end sags overnight or leans, compressor runs long or never, suspension warning light (Steering & Suspension)
• Timing belt due or history unknown, coolant weep at the front of the engine (Engine)
• Ticking from the engine on cold start that fades as it warms (Engine)
• Rust on the frame, or play and a torn boot at the lower ball joints (Frame & Body)
• Check engine light with P0171 and P0174 (both banks lean) (Fuel & Ignition)
• Shudder at 35–45 mph, flare between 2nd and 3rd, or a hard downshift (A750F) (Transmission)

All 11 Lexus GX 470 symptoms in the interactive troubleshooter →

General guidance from owner experience. Confirm torque specs, fluid capacities and procedures in the factory service manual. Brakes, steering and anything structural: if in doubt, have a qualified shop inspect it before driving.