A vehicle was presented for its first NCT test, and the front side lights were not operational. The workshop checked the 501 bulbs in both headlights, and they were not blown.

The vehicle was scanned for codes, and it came back with 2 fault codes.

• B114A Sidelamp control RH  
• B114B Position lamp control LH

Referring to manufacturers diagrams to investigate the circuit errors, it showed no side lamp circuits to the headlamps. All the other circuits had signals for low beam /high beam/ indicator and headlamp level control, but no wiring to the side lamps were present in the headlamp connectors.

But the Daytime Running Lamps (DRL) also did not work. So, the DRL circuits were next on the check list. And no circuit issues were found. Both DRL lamps were resistance checked, and it was then we noticed one was 9.6K ohms and the other 5.6K ohms.

And after questioning the customer, we learned that the car was an accident salvage. The DRLs had been replaced at the time of the repair, but they were not a matching pair.

A pair of DRLs were ordered for this 2019 model, and Vauxhall sent 2 options, “PWM” and “DMT Less”. The “DMT Less” lights for 2019 models were fitted, all codes cleared and the LED side lights and the DRLs returned to working normally.

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