Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Keyword 2000 Serial Data Circuit: Notes
The Keyword protocols utilizes a single wire bi-directional data line between the modules and the scan tool. The message structure is a request and response arrangement. Keyword 2000 is used for scan tool diagnostics only. The modules do not exchange data on these systems. They are two independent Keyword serial data circuits connected to data link connector (DLC) terminals 7 and 12. The following modules communicate with scan tool through Keyword 2000 serial data circuits:
Keyword serial data to DLC terminal 7
- Transmission control module (TCM), w/L61
- Engine control module (ECM)/powertrain control module (PCM)
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.