Paul1436215430 Posted March 1, 2020 Report Share Posted March 1, 2020 Hi Guys, Had an issue at a race meet at the weekend. no mechanical changes were made to the car nor wiring, or ecu settings. after what appears to be sustained periods on the brakes ( end of the straight) scenario it appears that the ecu is failing to reach target position for the Bosch DBW and is sitting the controller at max DC% until the ecu goes into fault with Code 84. which from having researched as much as i can on this before posting is because, at sustained high DC the controller will either be getting very hot or exceeding the maximum permit-able current. Im just hoping for some insights into what could have caused this as nothing has changed setup wise with the car. attached is a screenshot log (the actual log is too big to upload), of whats going on.throttle body is only a few months old and was a brand new genuine item. ecu is a G4+ Xtreme Black. Earlier in the log, you can see that the only way to get the ethrottle to re-activate was to shut the car down (kill isolator) then restart. Quote Link to comment Share on other sites More sharing options...
Adamw Posted March 2, 2020 Report Share Posted March 2, 2020 Can you attach the log and tune. Quote Link to comment Share on other sites More sharing options...
Paul1436215430 Posted March 2, 2020 Author Report Share Posted March 2, 2020 log attached. had to zip it to meet file size limit. log file.zip ecu-pre-ethanol-sensor-boost-bypass.pclr Quote Link to comment Share on other sites More sharing options...
Adamw Posted March 3, 2020 Report Share Posted March 3, 2020 You're right, it does appear to be shutting down due to over temp. However in most cases where it has shut down the motor duty cycle was only around -25% DC at the time, so assuming a typical motor load I would expect it should normally be happy to run all day at that. The periods that you see with it sitting at -80% DC is actually after it has shut off - you can tell as the spring pushes the TP back to 6% which is its neutral position. So something is making it run hotter than it should be. The logged ecu temperature looks fine so I think that leaves 2 other possibilities: The load connected to aux9/10 is higher than expected (low resistance). This could be a partial short in the motor windings or wiring etc. It wouldnt hurt to pull the aux 9 & 10 wires out of the ecu connector and measure the resistance across those two wires. I dont really know what to expect as I havent measured one for a long time but if it measured less than about 2ohms then I would probably research it a bit more to see if I could confirm what is normal. The second possibility would be an internal hardware issue such as the heatsink come unstuck or a bad connection/pcb track/solder join causing more heat than normal to be generated. If the motor resistance checks out then I would suggest you contact tech support to get the ecu checked out. Quote Link to comment Share on other sites More sharing options...
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