P1518
Electronic Throttle Module To PCM Communication
What it means
P1518. Electronic Throttle Module To PCM Communication. This Chevy-enhanced code applies to Silverado, Sierra, Tahoe, Yukon, Suburban, Avalanche.
Findings, check these first
- Corroded TAC module connector breaking serial data between the TAC module and PCM
- Chafed serial data wire in the harness along the left valve cover
- Failed TAC module internal serial interface on 2003-2006 full-size trucks
- Low system voltage interrupting TAC-to-PCM communication
Standard procedure
- Inspect and clean the TAC module connector pins; fretting corrosion is a known cause
- Wiggle-test the engine harness while watching TAC data on a Tech2/GDS2 scan tool
- Load-test the battery and verify charging voltage before condemning modules
- Replace the TAC module only after wiring and voltage test good
Look up another code
Press / to jump to the box. Chevy-enhanced powertrain, body, chassis and network codes.
Sources and review
Review: checked against the recorded source material.
- OBDII Code P1518 CHEVROLET - Electronic Throttle Module to PCM Communication | Engine-Codes.com
archived reference page (engine-codes.com via Wayback Machine)
Supports: code identity and Chevrolet application
Fetched directly. Exact title match. Model and year fitment remain curator claims.
Last updated 2026-09-13.
Report a correction for P1518. Include your vehicle, the issue and a source if you have one.