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Home >> Lexus >> 2020 >> LS 500 Base, AWD >> Repair and Diagnosis (Single Page) >> Restraints >> Air Bag, SRS >> Pedestrian Protection System - Diagnostic Codes (2 Of 2) & Symptom Tests >> Pedestrian Protection System >> DTC B1990: Short in Front Pop Up Hood Squib RH Circuit; DTC B1991: Open in Front Pop Up Hood Squib RH Circuit; DTC B1992: Short to GND in Front Pop Up Hood Squib RH Circuit; DTC B1993: Short to B+ in Front Pop Up Hood Squib RH Circuit [12/2017 - 10/2020] >> Description
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DTC B1990: Short in Front Pop Up Hood Squib RH Circuit; DTC B1991: Open in Front Pop Up Hood Squib RH Circuit; DTC B1992: Short to GND in Front Pop Up Hood Squib RH Circuit; DTC B1993: Short to B+ in Front Pop Up Hood Squib RH Circuit [12/2017 - 10/2020]: Description

The pop up hood squib RH circuit consists of the pedestrian detection ECU assembly and pop up hood lifter assembly RH.

The pedestrian detection ECU assembly uses this circuit to deploy the pop up hood when deployment conditions are met.

These DTCs are stored when a malfunction is detected in the pop up hood squib RH circuit.

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Test Mode / Check Mode
B1990 Short in Front Pop Up Hood Squib RH Circuit One of the following conditions is met:
  • The pedestrian detection ECU assembly detects a line short circuit signal 5 times in the pop up hood squib RH circuit during the primary check.
  • A pop up hood squib RH malfunction
  • A pedestrian detection ECU assembly malfunction
  • Instrument panel wire
  • Engine room main wire
  • Pop up hood lifter assembly RH
  • Pedestrian detection ECU assembly
Comes on Applicable
B1991 Open in Front Pop Up Hood Squib RH Circuit One of the following conditions is met:
  • The pedestrian detection ECU assembly detects an open circuit signal in the pop up hood squib RH circuit for 2 seconds.
  • A pop up hood squib RH malfunction
  • A pedestrian detection ECU assembly malfunction
  • Instrument panel wire
  • Engine room main wire
  • Pop up hood lifter assembly RH
  • Pedestrian detection ECU assembly
Comes on Applicable
B1992 Short to GND in Front Pop Up Hood Squib RH Circuit One of the following conditions is met:
  • The pedestrian detection ECU assembly detects a short circuit to ground signal in the pop up hood squib RH circuit for 0.5 seconds.
  • A pop up hood squib RH malfunction
  • A pedestrian detection ECU assembly malfunction
  • Instrument panel wire
  • Engine room main wire
  • Pop up hood lifter assembly RH
  • Pedestrian detection ECU assembly
Comes on Applicable
B1993 Short to B+ in Front Pop Up Hood Squib RH Circuit One of the following conditions is met:
  • The pedestrian detection ECU assembly detects a short circuit to B+ signal in the pop up hood squib RH circuit for 0.5 seconds.
  • A pop up hood squib RH malfunction
  • A pedestrian detection ECU assembly malfunction
  • Instrument panel wire
  • Engine room main wire
  • Pop up hood lifter assembly RH
  • Pedestrian detection ECU assembly
Comes on Applicable