B0503 - Short To Voltage Or BCM Open Internally In The RH DRL Relay Control Circuit

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3   
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Possible causes

  • Faulty Right Daylight Running Lamp (DRL) Relay
  • Right Daylight Running Lamp (DRL) Relay harness is open or shorted
  • Right Daylight Running Lamp (DRL) Relay circuit poor electrical connection
  • Faulty Body Control Module (BCM)

Possible symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

B0503 Description

The Body Control Module (BCM) provides control for the Right Daylight Running Lamp (DRL) relay circuit. The BCM grounds the RH DRL relay control circuit in order to energize the RH DRL relay and turn ON the RF turn signal. This allows the RF turn signal to be used for DRL and approach lighting functions. The BCM monitors the voltage level on the RH DRL relay control circuit. When the BCM commands the relay ON, the voltage level on the RH DRL relay control circuit should be low. When the relay is OFF, the voltage on the RH DRL relay control circuit should be high. If the BCM detects a voltage level other than expected, a malfunction is present and a Diagnostic Trouble Code (DTC) will set.
OBDII Code B0503 - Short To Voltage Or BCM Open Internally In The RH DRL Relay Control Circuit - AutoCodes.com

B0503 Information for specific makes

  • B0503 BUICK Short To Voltage Or BCM Open Internally In The RH DRL Relay Control Circuit
  • B0503 CADILLAC Short To Voltage Or BCM Open Internally In The RH DRL Relay Control Circuit
  • B0503 CHEVROLET Short To Voltage Or BCM Open Internally In The RH DRL Relay Control Circuit
  • B0503 GMC Short To Voltage Or BCM Open Internally In The RH DRL Relay Control Circuit

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B0503 Comments

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