RomRaider

Hi, hoping for some help. I am setting up a Bench ECU. I have the connections made, but no comms (using RR Logger). Comms confirmed to work with the ECU in the car, so I must be missing some connections with the Bench ECU.

ECU Connections:
Power (12V DC): B135 pin5, B135 pin6
Power (12V DC) with simple on/off switch to simulate ignition turning on: B137 pin15
SSM: B137 pin20
Ground: B135 pin1, B135 pin4, B137 pin1, B137 pin2

See diagrams from service manual
- ECUPinOut (as seen when looking at ECU which has male connectors)

- ECU Power pins

- ECU Ignition switch

- ECU SSM

- ECU Grounds


OBD2 Connections:
Power (12V DC): pin1
Ground: pin12, pin13
SSM: pin10

See diagram from service manual (as seen when looking at female OBB2 / data link connector)

For which car, ECU or CAL ID?

Oops, meant to put those details in the post.

My car is a 2005 Outback ADM MT CALID E2WG200G ECUID 4552164206. ECU part number is 22611-AK840. The bench ECU is the same ECU part number and came from a Liberty of similar age. I don’t have the CAL ID or ECU ID, will get it once I can get KLine comms working.

Did you power up your OBD interface? Should be also powered with 12v.

Control module power supply usually comes after ignition switch power via ign relay (ecu controlled), so maybe that will also mess up connection.

Thanks for the suggestions. Still no luck. What I've tried/checked:
- removed 'control system' grounds (B137 pin1, B137 pin2)
- checked for continuity from female OBD2 connector to Power, Ground, Kline wires
- checked again that the computer and VAG COM cable work by connecting to the Car (different ECU but same part number)

I'm not sure I understand SergArb's question... the setup is:
- PC with USB connected VAG COM cable terminating in male OBD2 connector (unmodified)
- above is plugged into female OBD2 connector which has a pigtail at the end of the wires
- A repurposed power supply transforms 240V AC from wall socket into 12V DC to provide +12V and Ground to the female OBD connector and ECU
- The pigtails from the female OBD2 are connected to the power supply +12V (pin1) and Ground (pin12, pin13). OBD2 Pin10, Kline, is connected to the ECU Kline (B137 pin20)
- The power supply also supplies +12V to the ECU (B135 pin5, B135 pin6) and to a switch (simulates turning key to ON) which goes to ECU B137 pin15
- The power supply ground is connected to B135 pin1, B135 pin4

One thing I noticed which seemed a bit odd... with the 12V power supply on, the Kline wire is at +12V when it is connected to the VAG COM cable (even if the VAG COM cable is disconnected from the PC and the ECU is not connected). So it appears the VAG COM cable gets +12V from the female OBD2 on pin16 (power), and sends back +12V to the female OBD2 on pin10 (KLine). Does that seem correct?

Any help greatly appreciated. I feel like this should be straightforward, and I'm probably missing something simple. Engine Wiring Diagram and ECM IO from FSM attached if that helps. Thanks!

Success for bench logging!

It turns out that one of the pins is different between the US model wiring diagram (what I was using) and the Rest-of-world wiring diagram (what I should have been using).

In case it helps someone, the pins required are:

ECU Connections
Power (12V DC): B135 pin5, B135 pin6
Power (12V DC) with simple on/off switch to simulate ignition turning on: B137 pin14
SSM: B137 pin20
Ground: B135 pin1, B135 pin4

OBD2 Connections:
Power (12V DC): pin1
Ground: pin12, pin13
SSM: pin10

One confusing element is that, at the time these cars were made, Subaru reversed the pin numbers for the OBD2 connector compared to what is normal. So, pin1 above (from Subaru wiring diagram) is what is normally called pin16.