DTC U2633-16: Light Control Module (LH) Power Supply Circuit (IG+) Malfunction (BCM): Outline

WARNING: This page is about a different car, the 2020 Mazda CX-30. However, it is still accessible from the selected car via links, so may be relevant.

DTC U2633:16 (BCM) DETECTION CONDITION AND POSSIBLE CAUSE

System malfunction location	Light control module (LH) power supply circuit (IG+) malfunction
Detection condition	The light control module (LH) (built into front combination light (LH)) power supply circuit (IG+) voltage is lower than the standard.
Fail-safe	Not applicable
Possible cause	IG1 relay No. 2 malfunction and headlight relay malfunction Front combination light (LH) connector or terminal malfunction Short to ground in front combination light (LH) power supply circuit (IG+) Front combination light (LH) internal malfunction Body control module (BCM) malfunction
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