Control Circuit Inspection

Open Check
1. Ignition "OFF"
2. Disconnect Brake Lamp Relay (DBC relay) and HECU connector.
3. Measure resistance between control terminal of brake lamp relay (DBC relay) harness connector and brake lamp control terminal of HECU harness connector.
  Specification: Approx. below 1Ω
  
  Fig 1: Measuring Resistance Between Brake Lamp Relay Control Terminal And HECU Brake Lamp Control Terminal
  Courtesy of HYUNDAI MOTOR CO.
4. Is the measured value within specifications?
  YES
  - Go to " 2Short Check" procedure.
  NO
  - Repair open in control circuit between the brake lamp relay and HECU and then, Go to "VERIFICATION OF VEHICLE REPAIR " procedure.
Short Check
1. Ignition "OFF"
2. Disconnect Brake Lamp Relay (DBC relay) and HECU connector.
3. Measure resistance between control terminal of brake lamp relay (DBC relay) harness connector and chassis ground.
  Specification: Infinite (∞ Ω)
  
  Fig 2: Measuring Resistance Between Brake Lamp Relay Connector Control Terminal And Chassis Ground
  Courtesy of HYUNDAI MOTOR CO.
4. Is the measured value within specifications?
  YES
  - Substitute with a known-good Brake Lamp Relay (DBC relay) and check for proper operation.
    If problem is corrected, replace Brake Lamp Relay (DBC relay) and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.
  NO
  - Repair short in control circuit between Brake Lamp Relay (DBC relay) and HECU, and then go to "VERIFICATION OF VEHICLE REPAIR " procedure.