ALDL Communications Issue
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2nd Gear
Joined: Jul 2025
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ALDL Communications Issue
I wanted to get some input on the issue with my car's serial data bus. (1995) My scanner cannot connect to the computer, however the car still runs fine with ebtcm code 72 showing. I disconnected the ebtcm and checked for an open circuit, but there was good continuity from that connector to pin 9 on the dlc (ALDL/obd port). When I have the car off and battery disconnected, I am measuring 2,200 ohms from pin 9 on the 16 pin connector to ground. This seems like there is a short to ground somewhere, but before I check the entire harness, I want to know what others are measuring form pin 9 to pin 4/5 (both are ground, engine metal also works fine).
