Where is the diagnostic port on a Lexus ls400?
The diagnostic port on a typical US-spec Lexus LS400 from the mid-1990s onward is the 16‑pin OBD‑II connector located under the driver’s side dash, near the knee area.
Understanding this location helps you quickly connect a scanner for codes, emissions readiness, and basic live data. Older LS400s and some non-US versions may not use the standard OBD‑II port, or may place diagnostic access elsewhere, so the exact spot can vary by year and market.
Finding the port on US-spec LS400s (1996–1997 and similar)
Below is a quick checklist of where to look and how to access the OBD‑II port on common LS400 configurations from the mid‑1990s.
- Open the driver's door and locate the knee bolster under the dash on the left side of the steering column.
- Look for a small removable panel or cover in that area; the 16‑pin DLC is hidden behind it.
- Gently pry the cover off to reveal a rectangular 16‑pin connector that accepts standard OBD‑II scanners.
The port is usually horizontally oriented and near the steering column, making it accessible without opening the hood. If you don’t see a port right away, check for a small plastic cover that you may need to pull or flip down.
Older LS400s and non‑OBD‑II configurations
For pre‑1996 LS400s or models intended for markets outside the United States, there is no universal OBD‑II port. Diagnostic access may be via a non‑standard connector or located in a different area, and scans often require a dealer tool or a dedicated service manual. If you cannot locate a standard 16‑pin port under the dash, verify your vehicle’s year, market, and whether it uses OBD‑I or a proprietary diagnostic interface.
If you can share your exact model year and market (US or other), I can point to the most likely location and, if needed, alternative diagnostic access points.
Summary
The simplest answer for most LS400 owners with late‑model, US‑spec cars is that the diagnostic port is the 16‑pin OBD‑II connector under the driver’s side dash, behind a small cover in the knee‑area near the steering column. Pre‑1996 models or non‑US variants may lack this standard port and require different access methods or a dealer tool. Always refer to the owner’s manual or service manual for your exact year and region to confirm the location.
