Pete_89t2 Posted September 20, 2020 Report Share Posted September 20, 2020 My Link G4+ Fury is installed on a modified single turbo FD RX7 that is running a GM DBW throttle. I can use some help troubleshooting an intermittent problem where the ECU flags a fault code #73, Aux 9/10 supply voltage. This happens very randomly - I can drive the car for several days and many miles with zero occurrences, then it may happen shortly after start up on the next drive or several miles into it. Usually when it does happen, I can use PCLink to clear the fault code and drive home with no problems, but sometimes that drill takes multiple iterations. Anyway, I've been logging data on every drive as I'm still tuning the car, and confirmed in the logs that when it does happen, my AUX 9/10 voltage does indeed drop to about 1.5V in the span of about 1 second. Based on this, I started looking for any possible open circuits or bad connections in the wiring harness and relays (main ECU power and E-throttle relay) that are associated with supplying power to AUX 9/10 from the hot and ground sides. No problems were found there; static continuity & resistance tests of the harness reveal no issues. Same story for voltage tests of the harness with the ignition keyed on but motor not running - I get a steady battery voltage at the AUX 9/10 power supply pin. I also tried to induce the fault with the car idling in the driveway by trying to tap on the relays, and wiggle/tug wires associated with the AUX 9/10 power circuit, but was unable to replicate the failure. The relays I'm using are pretty standard Bosch automotive 5 pin relays, rated at 30A for the NO contacts. The coils on them are not polarized; not sure if they have any diode protective circuitry that some relays have on their coils though. Any ideas on what to try next, or anything I'm missing? I was thinking of just replacing the relays to see if that changes anything. Thanks in advance! Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 20, 2020 Report Share Posted September 20, 2020 Can you give us a PC log with some heavy throttle/foot movements - engine doesnt need to be running. The error 73 maybe a tune issue rather than wiring issue - if the ECU shuts off the E-throttle relay due to errors/safety checks then this error can appear. Quote Link to comment Share on other sites More sharing options...
Pete_89t2 Posted September 20, 2020 Author Report Share Posted September 20, 2020 Thanks Adam, I hope you're on to something - tweaking the tune sure beats messing with wiring! I created a PCLink log as requested. Car was not running, the 1st few throttle movements were on the slow/gradual side, and as the log progresses they get faster & faster, 0 to 100% and towards the end they were more varied as far as start % and end %, but I moved the throttle as fast as my right foot let me. It's about a minute of data, but apparently too big to attach within the 291Kbyte limit the forum has. So instead I posted it on Google Drive - see if you can get to it from this link: https://drive.google.com/file/d/1Z72aUzf-uk_w4X6EPwEnJFTFBNKLl7xh/view?usp=sharing Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 21, 2020 Report Share Posted September 21, 2020 Ok it all looks happy in that log. But things might be different when the engine is running and there is boost etc. So my next suggestion is to set up ECU logging like below and next time it plays up, down load the log out of the ecu as soon as you can. The ECU will have enough memory to hold about the last 1.5hrs of running set up like this. This may give us more clues. Set up like below except for aux 8 status - replace that with whichever aux controls your DBW relay. Quote Link to comment Share on other sites More sharing options...
Pete_89t2 Posted September 21, 2020 Author Report Share Posted September 21, 2020 Got it, thanks - I'll set up the ECU logging as described and share a log next time it acts up. Quote Link to comment Share on other sites More sharing options...
BeallJK Posted September 21, 2020 Report Share Posted September 21, 2020 Interested to see how this plays out. I will get fault #73 at times as well. Thanks again Adam for your help! Much appreciated! Quote Link to comment Share on other sites More sharing options...
Pete_89t2 Posted September 21, 2020 Author Report Share Posted September 21, 2020 Hi Adam, I got lucky today and managed to get the code 73 error to repeat. Here's a link to the ECU log on Google drive with the data you requested: https://drive.google.com/file/d/1fWPveBln3SQHru_cT-2_SkuL0Wa5fRps/view?usp=sharing I recalled that while I was previously testing the cruise control function, the code 73 error would be more likely to occur, so that's what I did to try to instigate the error today - toward the end of the log, I set the cruise control at a set speed, cancelled & resumed cruise, and not long after that the code 73 occured. It was accompanied by a code 75 fault this time too. If the ECU log doesn't provide sufficient data, I was also logging on my laptop at the same time - time index in that log where the code 73 failure occurs is at approximately 17min-40sec in. Here's a link to that much larger file: https://drive.google.com/file/d/13SXDvQd1gO757qOT9WCUTkylXImu4qQq/view?usp=sharing Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 21, 2020 Report Share Posted September 21, 2020 Yeah, ok this is just a PID/tune issue. You can see in this log under certain conditions the E-throttle gets an unstable oscilation in it, which causes the TP/Target error accumulator to count up with no time to recover. Once it reaches 100% it shuts down the E-throttle relay. If you attach your tune I might be able to suggest a change. Quote Link to comment Share on other sites More sharing options...
Pete_89t2 Posted September 21, 2020 Author Report Share Posted September 21, 2020 Excellent, thanks for the help Adam! I attached the tune file I was running at the time, looking forward to any PID suggestions you may have. Baseline Tune -v1 (post rewire - AS-IS v4 9-21-2020).pclr Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 22, 2020 Report Share Posted September 22, 2020 E-throttle PID is always hard to guess without experimentation, but based on the numbers in the help file for the LS throttle I would start by dropping the Integral back to 0.05. If that doesnt help try dropping proportional back to 6.5 Quote Link to comment Share on other sites More sharing options...
Pete_89t2 Posted September 22, 2020 Author Report Share Posted September 22, 2020 Ok, so then change the "I" gain in the e-throttle settings from the existing 0.125 to 0.05 and do some testing, and if that doesn't improve things, drop the existing "P" gain from 7 to 6.5 as well. For testing to see if the changes are trending in the correct direction, I was thinking I should drive the car with the cruise control, which seems to be a factor that instigates the instability, and see what the TP/target error accumulator data tells us - lower #'s being better. Sound like a plan? Quote Link to comment Share on other sites More sharing options...
Adamw Posted September 22, 2020 Report Share Posted September 22, 2020 Yes, that would be the plan of attack. Quote Link to comment Share on other sites More sharing options...
Pete_89t2 Posted September 23, 2020 Author Report Share Posted September 23, 2020 Well I think this problem is solved! Took a few drives yesterday & today and had a look at the data. This was after just changing the "I" gain for the E-throttle as Adam suggested. Bottom line is the TP/target error accumulator doesn't go any higher than 10 now, and most times it stays at zero. In fact the only time it rises above zero is when I use the cruise control - the blip you see in the time plot image below occurred right after I hit the "cancel" switch on the cruise control (cruise was set at approx. 60MPH at the time), and I took over control of the accelerator pedal. I'll get a similar magnitude blip in the data when I set the cruise speed, or hit the resume/accel. button. Thanks again Adam! Quote Link to comment Share on other sites More sharing options...
BeallJK Posted June 15, 2022 Report Share Posted June 15, 2022 I previously reported intermittent problem with ECU Fault Code 73 AUX 9/10 Supply Error and it seems to have put my 2003 350z (VQDE) into limp mode / no start. I am about 3minutes into an engine refresh and I am still 'flushing' the block prior to break-in oil. I have run the car two or three times now for around 30seconds to 60seconds to check for leaks, make sure I have oil pressure, make sure everything is going as expected. Everything was fine and I shut the car down. When I attempted to restart the car I got the following ECU Fault Codes: ECU Fault Code 14 AN Volt 2 Below Error Low Value ECU Fault Code 73 AUX 9/10 Supply Error ECU Fault Code 76 TP(main) / TP(sub) Tracking Error and the generic error that the engine is limited to 1800rpm (it should be noted that I cannot get the engine to catch/start after cranking) I have about 13volts on the battery normally and it drops down to 8.5 to 9volts during cranking. I attached a quick datalog for reference of two cranking sessions with no start/no catch along with the tune that is currently in the car. It should be noted that it does sound like the car wants to start but doesnt and will just sputter and die Verified Fuel Pressure / Fresh fuel in the tank This is the same tune I used about a year ago when I took the engine out of the car for a engine rebuild Checked fuses, relays, made sure everything was plugged in Swapped in another TB and no change Any guidance / assistance would be appreciated! Error 14 73 76.llg warm up phase 3.pclr Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 15, 2022 Report Share Posted June 15, 2022 You have something wrong with the signal into AN Volt 2 which is the TP Main sensor. It is sitting at less than 0.05V, where as according to your TP calibration 0.455V should be the lowest it can go when the throttle is fully closed. Quote Link to comment Share on other sites More sharing options...
BeallJK Posted June 16, 2022 Report Share Posted June 16, 2022 Thank you Adam - Great insight as always. I secretly love how Link does their own CEL nomenclature with their own fault codes. I had some time this evening to dig into Nissan’s factory service manual and back-traced it to the throttle control in the IPDM. Swapped a relay and the car is running (rough) and the faults have ceased. Thank you again! Quote Link to comment Share on other sites More sharing options...
Cnote0ne Posted July 1, 2022 Report Share Posted July 1, 2022 On 6/16/2022 at 2:32 AM, BeallJK said: Thank you Adam - Great insight as always. I secretly love how Link does their own CEL nomenclature with their own fault codes. I had some time this evening to dig into Nissan’s factory service manual and back-traced it to the throttle control in the IPDM. Swapped a relay and the car is running (rough) and the faults have ceased. Thank you again! Hi BealJK, I'm having the same issue after doing the 75mm throttle body mod on my 350z (VQDE). I get the fault code 73 as soon as I turn the key to on position. I see a low voltage error in the ECU Status. Which relay did you swapped? My battery sit at 12 v ign/off and 14 v ign/on except when fault code hit it...drops to ~.4 v. Quote Link to comment Share on other sites More sharing options...
BeallJK Posted June 1, 2023 Report Share Posted June 1, 2023 Grrrrrrrr ... for what it's worth ECU Fault 14 (AN Volt 2 Low) and ECU Fault Code 76 (TP(main) / TP(sub)) Tracking Error have come back. The car has sat for about 3 or 4 months as I have been working on another car and life has just gotten super busy. With the warmer weather the car starts and cranks easier even with subpar starting parameters. Adam - are the GM Throttle Body Settings (above) applicable to Nissan as well? For what it's worth - I have sensor 5v power and sensor ground confirmed I have continuity between the throttle body and the ECU connectors When I cycle the ignition I can hear the throttle body blade move No issues with the APP sensor My AN2 Voltage Main is stuck at 1.00volt and status is 'Input at 0v/gnd' On 7/1/2022 at 8:04 AM, Cnote0ne said: Hi BealJK, I'm having the same issue after doing the 75mm throttle body mod on my 350z (VQDE). I get the fault code 73 as soon as I turn the key to on position. I see a low voltage error in the ECU Status. Which relay did you swapped? My battery sit at 12 v ign/off and 14 v ign/on except when fault code hit it...drops to ~.4 v. I swapped out the relay in the IPDM - I can get a picture for you if you like. Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 1, 2023 Report Share Posted June 1, 2023 1 hour ago, BeallJK said: Adam - are the GM Throttle Body Settings (above) applicable to Nissan as well? No. 1 hour ago, BeallJK said: My AN2 Voltage Main is stuck at 1.00volt and status is 'Input at 0v/gnd' This means the voltage on the AN volt 2 pin is below the "Error low" that you have set on AN Volt 2 (0.05v in out base map), so it is defaulting to the error value which looks like it is set to 1.00V. So start by measuring the voltage on pin 4 of the throttle body, if you have 0V there then the TPS has died, if it is outputting the expected ~0.5V then you have a disconnection between here and the ANVolt 2 pin at the ecu. Quote Link to comment Share on other sites More sharing options...
BeallJK Posted June 1, 2023 Report Share Posted June 1, 2023 10 hours ago, Adamw said: No. This means the voltage on the AN volt 2 pin is below the "Error low" that you have set on AN Volt 2 (0.05v in out base map), so it is defaulting to the error value which looks like it is set to 1.00V. So start by measuring the voltage on pin 4 of the throttle body, if you have 0V there then the TPS has died, if it is outputting the expected ~0.5V then you have a disconnection between here and the ANVolt 2 pin at the ecu. Thank you for the great explanation Adam - made perfect sense and I was able to follow your directions. I did not make any changes to the PID control for the TB It should be noted that I was having this issue on my original throttle body (from the factory in 2003) and I swapped it out with another Hitachi/Nissan OEM near-new replacment and it gave me the same issue. Link says something may have something jammed-up in the butterfly valve so I cleaned it well and it came back good. I was getting the ~.7volts and 4.4volts on each sensor circuit. Car started up and ran rough and Im still getting codes. It appears my throttle position is pegged at 100% with no movement (I dont immediately know why). APP sensor is acting normal. Im not sure if the actual butterfly valve is 100% opened or if the sensors are giving me fits or if I broke something (Something I’m going to check though? If anyone wants to take a look at the short data log it is attached - as always much appreciated! TP 100% Log.llg Quote Link to comment Share on other sites More sharing options...
Adamw Posted June 2, 2023 Report Share Posted June 2, 2023 There are no fault codes and your AN Volt 2 is reporting the correct voltage in the log. So it looks like you just haven't recalibrated the TPS after changing the throttle or fixing whatever caused the incorrect voltage. The "running rough" is just because overrun fuel cut is bouncing on and off. This is because the throttle is sitting in its natural disabled position. Quote Link to comment Share on other sites More sharing options...
BeallJK Posted June 2, 2023 Report Share Posted June 2, 2023 Thank you for reviewing my datalog - I am very grateful to have your help. I will recalibrate the TP and report back. Quote Link to comment Share on other sites More sharing options...
BeallJK Posted June 8, 2023 Report Share Posted June 8, 2023 Chased the issue back to the IPDM and it was a faulty relay. Put a relay in it from another IPDM that I had on the shelf. My Aux 9/10 CEL has gone away (12volts on the TB motor circuits). Quote Link to comment Share on other sites More sharing options...
helloimguo Posted January 13 Report Share Posted January 13 HI IM CURRENTLY EXPERIENCING THE SAME ISSUE WITH FAULT 73 COMING ON CAN ANYONE HELP ME PLEASE I ALREADY SWAPPED THE THROTTLE BODY, TPS, NEW BATTERY, NEW ECM RELAY. RECALIBRATED THE NEW THROTTLE BODY, I CANT FIGURE OUT WHAT ELSE COULD BE THE ISSUE.. ATTACHING A LOG OF THE CAR BELOW https://drive.google.com/file/d/1U4vho3rphiZhE26W4FtInJzDTRt2itmd/view?usp=drive_linkhttps://drive.google.com/file/d/1U4vho3rphiZhE26W4FtInJzDTRt2itmd/view?usp=drive_link Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 14 Report Share Posted January 14 Your file shares are restricted, go back into the share settings and set them to "anyone with link". Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.