HDD 156 - Heavy Duty Diesel Electrical/Electronic Systems Level II

1. Complete Level 2 HDD NATEF tasks related to Battery Service as listed below
   1. Charge battery using appropriate method for battery type.
   2. Inspect, test, and clean battery cables and connectors; repair or replace as needed.
   3. Jump start a vehicle using jumper cables and a booster battery or appropriate auxiliary power supply using proper safety procedures.
   4. Perform battery capacitance test; determine needed action.
   5. Identify and test low voltage disconnect (LVD) systems; determine needed repair.
2. Complete Level 2 HDD NATEF tasks related to Starting System as listed below.
   1. Perform starter circuit cranking voltage and voltage drop tests; determine needed action.
   2. Inspect and test components (key switch, push button and/or magnetic switch) and wires and harnesses in the starter control circuit; replace as needed.
   3. Inspect and test, starter relays and solenoids/switches; replace as needed.
   4. Remove and replace starter; inspect flywheel ring gear or flex plate.
3. Complete Level 2 HDD NATEF tasks related to Charging System Diagnosis and Repair as listed below.
   1. Test instrument panel mounted volt meters and/or indicator lamps; determine needed action.
   2. Identify causes of a no charge, low charge, or overcharge problems; determine needed action.
   3. Inspect and replace alternator drive belts, pulleys, fans, tensioners, and mounting brackets; adjust drive belts and check alignment.
   4. Perform charging system voltage and amperage output tests; perform AC ripple test; determine needed action.
   5. Perform charging circuit voltage drop tests; determine needed action.
   6. Remove and replace alternator.
   7. Inspect, repair, or replace cables, wires, and connectors in the charging circuit.
4. Complete Level 2 HDD NATEF tasks to Related Electrical Systems as listed below.
   1. Identify causes of constant, intermittent, or no horn operation; determine needed action.
   2. Inspect and test horn circuit relays, horns, switches, connectors, wires, clock springs, and control components/modules; repair or replace as needed.
   3. Inspect wiper motor transmission linkage, arms, and blades; adjust or replace as needed.
   4. Inspect and test auxiliary power outlet, integral fuse, connectors, terminals, wires, and control components/modules; repair or replace as needed.
   5. Inspect and test cruise control electrical components; repair or replace as needed.
   6. Inspect and test switches, relays, controllers, actuator/solenoids, connectors, terminals, and wires of electric door lock circuits.
   7. Check operation of keyless and remote lock/unlock devices; determine needed action.