6R 1.2 Throttle Actuator Control Motor Open Circuit

[vwgtitls16]

Hi all,

Having an intermittent fault occur in the last couple of days and looking for some next steps to try. The fault is occurring intermittently during start-up, it hasn't shown up whilst driving. Car goes into limp home mode with EPC, traction control and tyre pressure MIL lights illuminated. Reader comes back with just 1 fault: 10484 - Throttle Actuator Control Circuit P2100 00 [172] - Open Circuit MIL ON - Intermittent - Confirmed - Tested Since Memory Clear. I can switch off ignition, restart and the fault will go away without any driving. Driving without the fault is normal, idles fine and no issues with wide open throttle so definitely makes me think it's something electrical.

I've removed and inspected the harness connector on the throttle actuator and no signs of anything obvious, same with the pins on the body itself. The throttle plate itself looks clean and again nothing obvious. Also disconnected and inspected the accelerator pedal connector as I'd read this could be linked but again nothing obvious and didn't help. Removed and blew out the connectors on the ECM and no signs of any damage/bent pins/connectors etc.

I feel the next step is checking voltage at the pins for any open/shorts but I'm not sure on the pin assignment for the 6-pin connector. Could it also be something as simple as the battery but wouldn't this show up elsewhere too?

Anybody had this before or have any useful suggestions on what to try next? Many thanks in advance!

Polo 6R 1.2
Engine Code: CGPB

[iichel]

Is it a 1.2 Tsi or a cgpb engine? Cgp are 1.2 3-cylinder engines with 60-75 hp

[vwgtitls16]

It's a CGPB engine, post edited accordingly, apologies!

[iichel]

The fault is flagged as intermittent so it might be something that occurs very rarely. If the car drives fine, I would not worry too much. Looking at the diagram, it's unlikely to be the ECU since that shares the power supply to shared components.

My guess would be a faulty actuator.

[Brian422]

Intermittent problem could be due to Throttle Body sensors; Worn or contaminated finger or track.

Worth a watch:-

https://www.youtube.com/watch?v=fdLA5pXUkk4

[amer6R]

I also suspect the gear mechanism inside is worn