BMW E92 M3 LCI brake-light LEDs partly unlit
hitthelights asked why part of the passenger-side brake-light LEDs remained dark after replacing resistors and the lamp. His follow-up photographs document the question, while coding and wiring suggestions remain unconfirmed.
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Replacing the resistors and lamp did not change the symptom
M3Post member hitthelights reported that only part of the passenger-side rear-lamp LEDs lit when he braked. He said the driver-side lamp lit fully and all LEDs came on with the tail lights. He believed the conversion used resistors and had replaced both the resistors and the complete lamp, but the symptom persisted. He reported no related warning light and asked for advice.
The owner clarified that he meant columns, not rows
After Reddevils7 questioned the initial description of three LED rows, hitthelights corrected it to three columns: approximately half the LEDs horizontally. He explained that he had bought the car with these lamps already installed and later described them as OEM lamps. Those are the owner’s descriptions, not an independent verification of their manufacturer or wiring.
Photographs added to show the brake-light question
hitthelights supplied two photographs to show what happened when he pressed the brake, then added another while asking whether wiring was responsible or whether two passenger-side lamps could have the same LEDs out. The photographs retain their original order and framing. The owner did not report a confirmed cause or successful repair in the reviewed exchange.
Coding and the adapter harness were discussed
RocketyMan suggested that the FRM should be coded for LCI lamps. Reddevils7 cautioned that the partial-illumination symptom did not match the coding symptoms he described and questioned the lamps or wiring. RocketyMan later asked which adapter harness was fitted and proposed comparing the adapters and checking their connections. These are forum suggestions; no completed test or diagnosis is established here. Later measurements and photographs from m3.mrk concern a different car and are not presented as findings from hitthelights’ E92.
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