Originally Posted by Alta_Racer
There appear to be 5 grounds to your ECU. 1k 2a 2b 2c 2d. Be SURE they are GOOD grounds. This is not a job for an ohm meter.
1a and 1b are batt positive and keyed positive respectively. keyed power comes from the main relay. both these powers should be checked through the headlight to ground, to be sure they are good.
Tests complete. I have power at 1a and 1b. I have ground at 1k, 2a, 2b, and 2c. No ground at the 2d pin when the key is in "run" or "start". Looking at page 9 here
, it looks like 2d (BLK/BLU) is the ground for the following components:
- Heated oxygen sensor
- Mass Airflow Sensor (replace with the Link's MAP sensor at this point)
- Engine Coolant Temperature Sensor
- EGR Valve Position Sensor
- Throttle Position Sensor
The MAP, coolant temp, and throttle position sensors all get readings on the Link keypad, so they appear to be good. Any ideas on how to identify/isolate the issue to one of these components?
As always, you guys help is sincerely appreciated.