Test J: the Defrost System Is Inoperative - Front Windshield

PINPOINT TEST J: THE DEFROST SYSTEM IS INOPERATIVE - FRONT WINDSHIELD

J1-J3:

J3-J4:

J5-J7:

J7-J9:

J9-J11:

J12-J14:

J14-J15:

J16-J17:

Normal Operation
The heated windshield feature only operates when the engine is running. The heated windshield switch is provided ground through circuit GD145 (BK/BU) and the indicator is supplied ground through circuit GD138 (BK/WH). When the switch is ON, ground is supplied to the smart junction box (SJB) from the switch through circuit CRD08 (GN/OG). When the SJB commands the heated windshield ON, the SJB supples voltage to the RH and LH heated windshield relay coils and the heated windshield indicator through circuit CRD03 (BU/GN). The RH and LH heated windshield relay coils are grounded through circuit GD141 (BK/BU).

The right and left heated windshield relays are provided voltage through circuits (LH) SBB08 (VT/RD) and (RH) SBB09 (RD). When the relays are energized, voltage is provided from the relay to the heated windshield grids through circuits (LH) CRD10 (BN/WH) and (RH) CRD11 (YE/VT). The heated windshield grids are grounded through circuit (LH) GD136 (BK/GN) and (RH) GD141 (BK/BU).

Possible Causes
- Fuse(s)
- An open in circuits CRD03 (BU/GN), CRD08 (GN/OG), CRD10 (BN/WH), CRD11 (YE/VT), GD136 (BK/GN), GD138 (BK/WH), GD141 (BK/BU), GD145 (BK/BU), SBB08 (VT/RD) or SBB09 (RD)
- A short to ground in circuit CRD03 (BU/GN)
- Heated windshield relay
- Heated windshield switch
- SJB