Aaron C Posted December 6, 2020 Report Share Posted December 6, 2020 Hello everyone, I've been a lurker for awhile, but I've finally decided to create an account to learn more about this management system. I have an RB26 sitting in an S14 chassis. I made the mistake of doing too much at one time and just about every aspect of the car has been changed. For the initial start, I loaded up the base map and scaled the injectors for the ID 1700's and set up the Platinum Racing Products cam and crank trigger kit. The first attempt was a bit lackluster with a crank no start scenario. I noticed that I wasn't getting oil pressure or fuel pressure through the ECU, but I knew that I had pressure on both from a mechanical verification. I disconnected the ECU and calibrated calibrated the Fuel Pressure, Oil Pressure, Flex Fuel, and Wideband sensors. Once I reconnected it, I am no longer getting a trigger signal from the cam or crank. I've searched through the interwebs and verified the previous recommendations (double checked DIP switches, hit F12 to monitor triggers). Now I'm getting 2 no's on the trigger signals and zero RPM reading even when I've loaded up a previous map. I've included a copy of my map and a log from the first start attempt. The battery was a bit low on this attempt due to having everything on for initial set up hence the low rpm at 30 seconds. If someone has some spare time, would you mind taking a quick look to see if anything jumps out. RB26 w-PRP triggers.pclr First start attempt.llg Quote Link to comment Share on other sites More sharing options...
Adamw Posted December 6, 2020 Report Share Posted December 6, 2020 Your trigger setup looks ok assuming they are the 3 wire hall sensors, so there should be a signal. What you can do to diagnose is unbolt the crank sensor (leave it plugged in), and with ign on, while watching trigger signal runtimes you can wave a spanner or some other iron object past the sensor and the trigger signal runtime should show yes. If no joy with that then check with a multimeter there is 12V at the sensor and you can also check if there is a 0-5V signal coming out of the sensor when you wave the metal past it. Quote Link to comment Share on other sites More sharing options...
Gsab Posted December 6, 2020 Report Share Posted December 6, 2020 I am running the PRP 36-2 setup. I would suggest you lower your trigger filtering to 1. I had a Cherry hall from PRP fail on me. Replaced it and all was well again. The failure was within a few days of getting the engine started. You running the 12 tooth setup ? Funnily enough, also RB26 in a S14..... *Just to add-PRP 36-2 trigger offset is 284 deg.* Quote Link to comment Share on other sites More sharing options...
Aaron C Posted December 6, 2020 Author Report Share Posted December 6, 2020 Adam, You're correct that they're 3 wire sensors. Once I started having this issue, I went ahead and confirmed 12V at the harness, but I haven't checked voltage coming back out. I'm just really confused that I was getting a signal before, but nothing anymore. Hence why I thought maybe I had accidentally changed something when the sensor parameters were getting set up. Thank you for the input though. Knowing that the ECU configuration looks good and so I need to start looking in other areas gives me a bit of solace. Gsab, Yeah I'm running the 12 tooth kit on mine. Against my better judgement I completely built the car in one go as opposed to doing it slowly. Now I'm not entirely certain on where the failure point is haha. I've had some issues with the Wiring Specialties harness (again) and so I'm wondering if something is going on there instead of with the trigger kit. When you had the PRP sensor fail on you, were you still getting a signal on the other trigger? Quote Link to comment Share on other sites More sharing options...
Gsab Posted December 7, 2020 Report Share Posted December 7, 2020 Yes, I was. Crank trigger was perfect, cam sync was gone. Quote Link to comment Share on other sites More sharing options...
Aaron C Posted December 7, 2020 Author Report Share Posted December 7, 2020 I went out today and did some more looking at the sensors. I'm getting ground, 12V, 4V, 4V across the pigtail from the chassis side. With the connections tight, I ran an allen key over the two sensors with no effect, still 4V across the 1° and 120° signal wires. I was under the assumption that as the tooth passes over the sensor, it was to complete the circuit to send voltage to the ECU which would indicate position? Quote Link to comment Share on other sites More sharing options...
Adamw Posted December 7, 2020 Report Share Posted December 7, 2020 The 4V is coming from the trigger pull-up in the ECU. Most common hall sensors have a "sinking output", so when you place metal in front of the sensor the signal wire is effectively connected to ground, so you should see the 1° and 120° signal wires go to close to 0V when metal is in front of the sensor. Quote Link to comment Share on other sites More sharing options...
Aaron C Posted January 7, 2021 Author Report Share Posted January 7, 2021 RB26 w-PRP triggers.pclr A bit of an update.... I suspected I may have received a bad cam sensor, so I ordered another one. Once it arrived, I verified voltage on the harness side of things and got: Ground / 12V / 4V / 4V This new sensor did not change voltage as my tool passed over it. Thinking it was highly unlikely, but not impossible, I borrowed another sensor to just plug in and check. This also did not have a voltage change during the test through the harness. Since I'm getting the appropriate voltage to the sensors, I thought it HAS to be something with the ECU. Lurking through the forums again, I opted to try changing the trigger settings to the Subaru V1-6; store and power cycle. Once I changed back, I was still not getting any registration from the triggers. I verified my the wiring and triggers again, but I'm still not having any luck getting a signal from these sensors. A bench test of the crank sensor shows that it is working correctly, the cam sensor won't display a voltage change at all. I'm just about out of ideas regarding how to get this thing to fire. I'd really hate to ditch this set-up for the OEM CAS, but I can't think of anything else at the moment. Does anyone happen to see anything that I may have overlooked? Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 8, 2021 Report Share Posted January 8, 2021 How are you testing the voltage out of the senor, with a multimeter? What happens if you plug the cam sensor in to the crank wiring? Quote Link to comment Share on other sites More sharing options...
Aaron C Posted January 8, 2021 Author Report Share Posted January 8, 2021 9 hours ago, Adamw said: How are you testing the voltage out of the senor, with a multimeter? What happens if you plug the cam sensor in to the crank wiring? I'm testing with a multimeter. I don't have a second set of hands where I'm at, so I've been trying to do things solo. I used a pair of spade connectors and clipped my multimeter into them. I then added a 300mm lead to each connector and soldered some mechanics wire onto the end and inserted these into the back of the connector on the ground and on the signal wires. With the multimeter set up, I am passing a tool over the sensor to simulate cranking and measuring the 4V value to check for a voltage drop. The 120° signal sees a voltage change as the tool passes over the sensor, but the 1° sensor does not change at all. The link software states that its not receiving a signal at all from either of these hall sensors. 9 hours ago, Adamw said: What happens if you plug the cam sensor in to the crank wiring? I also thought that maybe the signal was being received incorrectly, so last night I swapped pins on the connector and did not see any change in voltage from the cam sensor. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 8, 2021 Report Share Posted January 8, 2021 So does the crank and cam sensor not have the same connector? It looks like you have a DTM3 on the crank sensor in the pick above? So cant you plug the cam sensor into that? Quote Link to comment Share on other sites More sharing options...
Aaron C Posted January 9, 2021 Author Report Share Posted January 9, 2021 I created a jumper harness that "Y's" from the factory CAS plug to each sensor. Then each sensor has about a 150mm lead going to the male connector. This was solely to facilitate ease of sensor replacement if/when the need arrived. Instead of rewiring things for the new sensor, I have my back up sensors ready with the DTM already crimped on. Removal and replacement can happen in just a couple minutes. You can kind of see the flying lead in the picture I've attached. When I switched the cam and crank signal, I simply swapped pins on my jumper harness for the 4V signal. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 9, 2021 Report Share Posted January 9, 2021 But you were saying above one of your sensors was showing a voltage change when you put metal in front of it right? And the other one doesnt? So that means you have at least one sensor that works and at least one wire that works. So unplug both sensors and swap them to the opposite leg of the Y piece. Moving the non-working sensor to the known working leg of the Y piece may help isolate where the issue is. Just swapping the signal wires etc doesnt eliminate anything down stream of the 4 way CAS connector. Quote Link to comment Share on other sites More sharing options...
Aaron C Posted January 9, 2021 Author Report Share Posted January 9, 2021 Correct, but swapping sensors didn't yield any change. Although I didn't physically swap the cam and crank sensors, I did replace the cam sensor 3 times without effect. Either way, the crank sensor is testing fine but the ECU isn't seeing any input from it. Leading me to believe that the issue lies with the ECU (whether its settings or something else). Regarding a known working area in the jumper harness, by swapping pins on the harness I effectively moved the non-working sensor to a known working point. So no matter what I can't get a cam sensor to work correctly. The harness has been tested, the sensors have been swapped, and I've played around with the settings within the ECU. I'm not sure what else to do except to remove it all and install the factory CAS and go from there. If there was a legitimate Link tuner in my area I'd just trailer it over there, but Link hasn't had an impact where I live. Nothing buy Haltech and AEM. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 9, 2021 Report Share Posted January 9, 2021 1 hour ago, Aaron C said: by swapping pins on the harness I effectively moved the non-working sensor to a known working point. Thats not what it sounds like from your description. By just swapping pins at the CAS plug, you are not eliminating the bit of wiring between the CAS plug and the cam sensor. It would be better to physically swap the crank/cam sensor to the opposite leg of the Y piece. Also, the pinout of the CAS plug in your annotated photo above is wrong. Power and ground are correct but the 1° signal (trigger 1) should be is next to the 12V and the 120° signal (trig 2) is the outside pin. Quote Link to comment Share on other sites More sharing options...
Aaron C Posted January 9, 2021 Author Report Share Posted January 9, 2021 The pins I swapped were the 1° and the 120° pins on the jumper harness that I made. So the 4V signal wire from the Cam was switched to the Crank and vice versa. So I have the crank as my 120° signal and the cam as the other based off what I read in the FSM. I tried to use the PRP online instructions, but they've changed since I got the kit and I'm wasn't sure which one to use. This afternoon I took off the sensors and installed the factory CAS which also eliminated the jumper harness. I followed the steps to use the factory optical sensor. Interestingly enough, I still don't have RPM and it said that it had input from trigger 2. I'm going to go ahead and OHM out the engine harness just to rule out possible damage, but it's a brand new harness from Wiring Specialties so I'm thinking it should be ok. The only other thing is the ECU. Maybe it's damaged, the settings are somehow off, or maybe it has an old firmware of something that is making it act weird. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 10, 2021 Report Share Posted January 10, 2021 If you have the original CAS connected can you do a triggerscope while cranking now. That may give some clues. Quote Link to comment Share on other sites More sharing options...
Aaron C Posted January 12, 2021 Author Report Share Posted January 12, 2021 I had already swapped the PRP trigger kit back on before I saw the message from you Adam. I did try a trigger scope with the PRP kit and I'm getting steady voltage without change. I also reinstalled the pclink software and did a firmware update. No change with my trigger issue. Then I loaded up the base R32 GTR map and made the changes for the triggers only to see if maybe it was a bad setting, but it had no effect. Still no rpm and Link is saying there isn't signals from either hall sensor. Next time I'm out there I'll do a continuity check from the bay to the ecu to rule out a wiring issue, but I'm just so confused right now. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 12, 2021 Report Share Posted January 12, 2021 Cant you just plug in the factory cas and spin it by hand or cordless drill etc? Quote Link to comment Share on other sites More sharing options...
Aaron C Posted January 13, 2021 Author Report Share Posted January 13, 2021 I'll try to figure out a way to do it. I'm kind of in the middle of nowhere and don't have another set of hands to assist. The USB cord won't reach into my bay and I can't fold the engine harness over with how everything is routed. Trigger scopes are new to me, so I'm still learning about how they work and what information they tell. If I just hit capture then run around and spin it by hand will it still get the necessary data? Either way, I'll give it a go and let you know how it turns out. Quote Link to comment Share on other sites More sharing options...
Aaron C Posted January 13, 2021 Author Report Share Posted January 13, 2021 I managed to do a continuity test on the wiring harness and everything checked out. Through some ingenuity and acrobatics I was able to get a trigger scope with the factory CAS. I'm not exactly sure what I'm looking for, but one of the signals doesn't look how I would think it should. When I attempted to do a trigger scope with the hall sensors, it didn't pulse at all on either of the triggers. The bench test showed the voltage drop on the crank trigger when I used a multi-meter, but none of the cam sensors saw a change during the same test. Trigger Scope Log 2021-01-13 4;25;11 pm.llg Here's a picture in case there is something wrong with the log. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 13, 2021 Report Share Posted January 13, 2021 It looks like trigger 1 and 2 are swapped (can be changed with the R34 dip switches) but there is something else a bit odd going on too. For the 120 deg signal we should actually see 6 different sized slots but there are 3 teeth with bits missing out of the middle of them where the voltage drops to zero intermittently and the widths of these teeth arent as precise as they normally are. The 1 deg signal also appears to be missing lots of teeth. Not sure if that is a bad connection somewhere or the CAS is dying. Quote Link to comment Share on other sites More sharing options...
Aaron C Posted January 13, 2021 Author Report Share Posted January 13, 2021 If anything, I would bet that the factory CAS is worn. I checked out the wiring though and it's good to go. As I was doing this test, it still registered as zero rpm through the ECU though and my PRP triggers aren't doing anything. This is definitely a weird situation and I'm not sure what else to look at. I can't help but feel that I've checked everything off the top of my head. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 13, 2021 Report Share Posted January 13, 2021 Its going to register 0 RPM until it gets a valid trigger signal that it understands. Since the 1deg and 120 deg signal are reversed and the 120 deg signal shows more teeth than it should then 0 RPM is expected. But it does prove that the ECU trigger inputs are working correctly and not damaged which was one of your earlier questions. Quote Link to comment Share on other sites More sharing options...
Aaron C Posted January 14, 2021 Author Report Share Posted January 14, 2021 Well that does put my mind at ease a bit, but confuses me even more then. I'm under the impression that the 1° signal is for the cam and the 120° signal is for the crank, so that is how I have them wired. I'm running an R32 engine/harness, so I have the DIP switches set to other. The wiring harness continuity checks out good with the DMM. If the trigger inputs are working correctly, that means that there has to be something wrong with the settings that I have...correct? So if trigger 1 (120°) is for the crank with a 12 tooth gear on it, pullup is on, and its set to falling. Trigger 2 (1°) is for the cam (pulse 1x), pullup on, and its set to falling. Neither of these triggers scope out, but yet the crank trigger bench tests good and the cam trigger(s) won't bench test at all. I've updated PClink and the firmware. Maybe retry calibrating the sensors? Quote Link to comment Share on other sites More sharing options...
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