Preliminary work: Diagnosis - Diagnostic Trouble Code (DTC) Memory 12

Preparation for Test: 1. Fuses OK. 2. Battery voltage >11 V. 3. Install model specific HHT module into HHT. 4. Connect the Hand-Held Tester (HHT) to X11/4, according to diagram, see section 0. Electrical wiring diagrams: Electrical Troubleshooting Manual, Model 129, Volume 2, group 80, Model 140, Volume 2, group 80, Model 170, Volume 2, group 80

Conventional tools, test equipment

Description	Brand, model, etc.
Multimeter 1)	Fluke models 23, 83, 85, 87, 88

1) Available through the MBUSA Standard Equipment Program.