Working with a Harley Davidson at the moment which can't produce a stable TPS signal
Replace the TPS sensor, but it's still all over signal wise...
Connected my Pico yesterday and from what i can see it got some interference? Or what am i looking at?
Attaching 2 images. The stable one is with engine off and the interfered one is with engine running...
This is an 2004 Ultra CVO 103" which has a history of missing/stutter at times, but not always.
Problem emerged when i was trying to map the ECU and discovered that the TPS was all over the place.
Done all the tests suggested by the Harley service manual, but can't find any faults there.
All relevant wiring to/from TPS is checked and can't find anything there.
Never had the need to check a Harley TPS with my Pico before, so in a way i'm curious to know if i'm looking at an ok waveform? Used the scope on several other TPS'es, but none of those have shown this kind of interference....
Despite your hard effort to solve this running issue i would still be looking at the wiring net and how the sensor gets power and ground.
I don´t have a wiring digram over that particular model but can see on other harley models that the ground connection from TPS sensor are connected to the oxygen sensor and the coolant temp. sensor and so maybe it could influcence the TPS sensor, if you have a bad oxygen senor or a bad coolant sensor.
You could try to temporary disconnect these sensors.
Hello buddy, it seems like some other circuit component is pulling TPS to ground so 1+ with wiring tests.
Just unplug other sensors in line and see whet happens.
Regards
You can scope power and ground to see if they are stable.
If they are, then place breakout leads between tps and the connector. Connect power and ground but leave the signal wire disconnected to see if the signal is good then.
I had to put the bike away for a few days (overswamped with other bike related work right now), but will continue next week.... I'll get back to you with my findings! Thanks all!!