Harry's GPS Suite Forum

Harry;

Couple of OBD questions...

In the expert settings tweaks menu, how do I know which throttle PID to choose? The default seems to work fine on my 2002 Mustang but reads 100% almost always on my 06' Jetta TDI. Do you know what settings are the most appropriate for the Jetta\Mustang? I am not able to get OBD data from the Jetta and HLT is stating an error, "OBD update rate." I have tried forcing sequential requests and auto excluding PIDs but have not had any success. I am pretty familiar with CAN communication standards and have implemented multiple busses in a single hybrid vehicle if it helps to discuss this.

Furthermore, I noticed that the throttle % displayed in the video from my Mustang is a bit quicker than the video. Is that adjustment made in the Sensor Delays - Any OBD? I am guessing I would make that zero since it is defaulted to 1s.

Is there any documentation which walks the user through the expert functionality?

Now, if only I could pull data at a rate greater than 3 Hz on the Mustang...

Thanks again!

-Nick

With your BT1 connected to your car with the engine running, switch to LapTimer's Sensor List, select the BT1 row, and select "Info". This gives you an overview on all PIDs provided by your car. To find the right throttle PID for your car, write down all throttle PIDs provided and try them one after the other. Usually Position D is a good bet.

In case you have the BT1 and LapTimer GrandPrix, do not select "Force seq. requests" as this will disable an optimization introduced for this OBD / LapTimer Edition giving you 1 or 2 Hz higher update rates that usual.

The OBD update rate warning means your update rate is lower that 1 Hz. The reason is either there is a problem retrieving valid data from the car, or it is because the car simply delivers at a low rate. I doubt a 06 Jetta features a CAN bus by the way, it will be a slower protocol.

A sensor delay of 0 would mean the sensor delivers the value exactly at the point in time it happens in reality. Even when considering 0 as a rounded 0.05 second delay, this is hardly possible for GPS or OBD. In case sensor data is ahead of the video, increase the video delay by e.g. 0.5 seconds (it is named Overlay Synchronization / Video) and try another overlay. All delays except the video delay are applied during recording, so the video delay is the only one easiest to test. Furthermore, the video delay is the one with the highest variance comparing devices to each other.

- Harry