Wiring and pinouts

Every wiring diagram and pinout is in the main documentation. This page is the index into it.

The GCU is a standalone transmission controller, so the pages that apply to it are the standalone controller pages. Where a diagram shows a connector, solenoid pad or sensor circuit, it applies to your unit as long as the transmission is the same.

Find your diagram

If you need Go to
The controller's own connector layout and pin functions Controller pinout
ZF 8HP wiring 8HP wiring
BMW dual-clutch (DKG / DCT) wiring DKG wiring
The GS7D36SG connector cross-reference GS7D36SG cross table
Setting up a dual-clutch transmission in software DCT standalone drivers
The diagnostic connector pinout OBD-II pinout

Shifters

Shifter integration covers every selector type — factory levers, paddles, sequential levers and analog PRND — and links the wiring and the configuration for each. The electrical side is the same whichever controller reads it.

Before you wire anything

Two things cause most of the damage that arrives for repair, and both are wiring decisions:

  • Suppress inductive loads. A solenoid or relay coil switched without a suppression diode puts a voltage spike back down the wire it was driven from. That spike is what kills output stages.

  • Get the supply and ground right before first power-up. Reversed polarity and a shared ground with a high-current path are the two most common causes of damaged inputs.

  • Give the supply an off-delay. The controller saves its state after the ignition drops, so BAT+/KL30 has to outlast the ignition by about 60 seconds or adaptation data is lost. Use a time-delay-off relay — the HELLA 5HE 996 152-131 is a known working part.

  • Do not wire KL30 to permanent battery. The controller has no low-power sleep mode — with KL30 present it keeps drawing 200–300 mA and will flatten the battery in hours. The relay is the answer, not a permanent feed.

The last two catch a lot of installations. Full detail: Adaptation data lost when the supply drops with the ignition.

Wiring concepts covers the system-level side — bus separation, power sequencing and grounding. It is written around the gateway hardware, but the electrical reasoning is the same.

Where to go next