Flow Chart No. 1

Flow Chart No.1- Symptom - Loss of GEM communication.

Step 1
Preliminary checks.




1. Check engine compartment maxi fuses A and B.
2. Check connections for clean, tight fit.
3. Check for loose or damaged wires.




4. Are components and wiring OK?

Step 2
Check fuse B for short to ground.
1. Key ON.
2. Inspect engine compartment fuse B.




3. Is fuse open?

Step 3
Check fuse A for short to ground.
1. Key ON.
2. Inspect engine compartment fuse A.




3. Is fuse open?

Step 4
Check open instrument panel fuse #25.




1. Inspect 7.5 A fuse #25.
2. Key OFF.
3. Remove engine compartment fuse B.
4. Using ohmmeter, check for continuity to a known ground.




5. Is continuity present?

Step 5
On-demand self test.
1. Connect NGS Tester #49 UNO1 131 to data link connector (DLC).
2. Select "Diagnostic Test Mode" and "On-Demand Self Test." Perform on-demand self test with ignition switch ON. Note any DTCs.
3. Press Cancel. Select "Retrieve/Clear Continuous DTCs." Retrieve continuous DTCs and note any DTCs.




4. Are self test and continuous DTC B1342 present?

Step 6
Check connector for open power circuit.




1. Check GEM 18-pin connector, pins 5 (W/Y) and 11 (W/Y) for loose terminals or pins back-out.




2. Does connector check OK?

Step 7
Check power circuit for open.




1. Check pin 11 (W/Y) at 18-pin connector for open.




2. Does circuit check OK?

Step 8
Check GEM ground point.




1. Check pins 14 and 26 at 26-pin connector or pin 18 at 18-pin connector to a known chassis ground.




2. Is continuity present?