Diagnostic Aids
Code 28 will set if PCM/TCM detects one of 2 "illegal" PSM combinations. See VALID PSM COMBINATION CHART table for various combinations. Check pass-thru connector for good contact.
VALID PSM COMBINATION CHART
| Application | A | B | C |
|---|---|---|---|
| Park | 12 | 0 | 12 |
| Reverse | 0 | 0 | 12 |
| Neutral | 12 | 0 | 12 |
| 4th | 12 | 0 | 0 |
| 3rd | 12 | 12 | 0 |
| 2nd | 12 | 12 | 12 |
| 1st | 0 | 12 | 12 |
| Illegal | 0 | 12 | 0 |
| Illegal | 0 | 0 | 0 |