Cluster M3 LED Retrofitting

Components soldered to Bosch cluster

Some of you asked if its possible to retrofit the M3 LEDs at the engine speed dial in a normal E46 cluster.

Well, now it is, sort of! If you have a Bosch cluster unit you are lucky, since these units share the same PCB with M3 clusters.

Its a hardware and software mod, so you need to source the following components and code the cluster afterwards for it to work.

• 1x TPIC6C595DR(Shift register)
• 1x CML0805X7R104KT50V (CAP, X7R, 0805, 0.1UF, 10%, 50V )
• 10x RMCF1206JT160R ( RES 160 OHM 5% 1/4W 1206 )
• 3x red LEDs 3528 PLCC2
• 7x yellow LEDs 3528 PLCC2

These parts can be ordered at your prefered electronics store. Also the amount of yellow and red may vary depending on your prefared scaling.

Cluster Modification Tutorial:

1. Disassemble your cluster carefully
2. Solder the shift register (green in Picture) first. It has same polarity as the shift register left to it. Just solder it like in the picture.
3. Solder the cap (purple) and resistors (blue) next. The polarity doesn't matter.
4. Finally solder the LEDs next. Red means yellow led, yellow means red LED - sorry for the misleading colors. Polarity is important here and GND is marked with the Black color.
5. Cut away the plastic over the LEDs
6. Assemble the cluster back together

Coding Tutorial:

• Set KVA_OELTEMP in your cluster to "aktiv"