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Home >> Infiniti >> 2009 >> QX56 AWD >> Repair and Diagnosis >> Electrical >> Body Electrical >> Power Control System >> Power Distribution System >> Ecu Diagnosis >> IPDM E/R (Intelligent Power Distribution Module Engine Room) >> Fail Safe >> Can Communication Control
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Can Communication Control

When CAN communication with ECM and BCM is impossible, IPDM E/R performs fail-safe control. After CAN communication recovers normally, it also returns to normal control.

If No CAN Communication Is Available With ECM

FAIL-SAFE CHART

Control part Fail-safe in operation
Cooling fan
  • Turns ON the cooling fan relay when the ignition switch is turned ON
  • Turns OFF the cooling fan relay when the ignition switch is turned OFF

If No CAN Communication Is Available With BCM

FAIL-SAFE CHART

Control part Fail-safe in operation
Headlamp
  • Turns ON the headlamp low relay when the ignition switch is turned ON
  • Turns OFF the headlamp low relay when the ignition switch is turned OFF
  • Headlamp high relay OFF
  • Parking lamps
  • License plate lamps
  • Tail lamps
  • Turns ON the tail lamp relay when the ignition switch is turned ON
  • Turns OFF the tail lamp relay when the ignition switch is turned OFF
Front wiper
  • The status just before activation of fail-safe control is maintained until the ignition switch is turned OFF while the front wiper is operating at LO or HI speed.
  • The wiper is operated at LO speed until the ignition switch is turned OFF if the fail-safe control is activated while the front wiper is set in the INT mode and the front wiper motor is operating.
Rear window defogger Rear window defogger relay OFF
A/C compressor A/C relay OFF
Front fog lamps Front fog lamp relay OFF