OEM Tachometer Not Working with Standalone ECU and Coil-on-Plug - Cluster Solder Repair and M1 Wiring

Electricalintermediate✓ OP Confirmed

Problem

OEM tachometer not receiving signal after switching to a standalone ECU (ECU Master EMU) with coil-on-plug ignition, replacing the original igniter which previously provided the tach signal

Tachometer not reading/responding at allNo tach signal despite standalone ECU tach output being configuredTachometer non-functional after igniter removal and coil-on-plug conversion

Root Cause

Three issues combined: the tach signal wire needed to be connected to the correct pin on the M1 connector behind the glove box (pin 4, black wire), the earth/ground wire (brown wire in M1) was not grounded, and a burned copper bridge inside the instrument cluster was broken and needed resoldering.

Confidence

Moderate confidence — Original poster confirmed this resolved the issue

View Original Thread →Posted June 2023 on SupraForums.com