[stevefed]

Hello everyone

I recently upgraded my
'74 Porsche 914 from 120v to 144v DC, and have been having this terribly frustrating issue, which I think was starting to happen before I made this voltage upgrade. Usually when I first turn the car on, everything works fine for a while. Then, after driving it a bit, when I come to a stop and go to accelerate, nothing happens. It's as if the controller is not getting any signal from the potbox. I have replaced the potbox, all relays, and all wiring, I've checked that the potbox is completely going to 0 when I release the pedal, there is no error indication on the Hairball interface for the Zilla controller, the main contactor is still connected, all 12 volt equipment on the car is working perfectly, it's just like the connection from the potbox to the Hairball is not happening. If I turn the car off and then back on it works, but then the more I do this the more it happens until eventually I have to turn it off and on each time I try to stop and then go. When the car works, it works perfectly, but obviously I can not drive it like this. I'm down to thinking it's possible an issue with the Hairball, the connecting cord from the Hairball to the Zilla controller, or something that I am missing somewhere. Any insight on any of this would be so greatly appreciated, it's really got me bummed out, since as I mentioned, when it works, it works perfectly and it's so much fun to drive! It just obviously not safe to operate with this seemingly random issue.

 

[piotrsko]

Sounds like it is getting too hot, JMHO

 

[stevefed]

Thanks for the reply, yea, I had thought that, but unfortunately, more and more is pointing to the reality that the motor is probably toast. It's not overheating, and can do this "shut down" at any given time, although it does get more common when the car has been on for a while. I'm going to put a voltage tester on the outgoing controller, just to make sure that's not what it is, but I think the motor, which is an Advanced 9" DC, and came used with the car that dates back to the 90's is the culprit. Bummer, it was probably the jump to 144v that finally did it in. And thanks to the taxman, it'll probably be a while until I can afford to be back on the road, boo-hoo. So close, yet so far.

 

[EVfun]

Can you plug into the Hairball with a laptop and use a terminal program to look for stored codes? Not all codes are errors that will shut things down. There is a way to use a jumper with an orange wire that came with the Hairball and read the codes out through a flashing light, but that is a pain. You can download the manual from Manzanita Micro if you don't have instructions for communicating with the Hairball.

 

[stevefed]

Thanks EVFun for the reply. With a meter yesterday I was able to figure out it is definitely the controller, which brings me to the same conclusion of what you're saying. I tried to install Putty on my laptop and plug into the ethernet port, but couldn't establish a connection. I've since ordered a usb to RS232 serial port adapter, after hours of driving to my local office depot, staples, walmart, etc. showed no one having one in stock. I'm much more of a mechanical guy then computer guy, so Putty is a real mystery to me. I've tried to find a way of hooking up more simpler to the Zilla. I bought all the stuff needed for an old Palm III, only to find out it didn't have the needed Ptelnet software installed, and no way of installing it. I've reached out to Rich over at Manzanita Micro multiple times to try to buy a tablet with software, but he's never followed through (not the best customer service I have to say) and stopped answering my emails. So yea, I think all I need to do is get into the Zilla and change the voltage and amperage limits, but jeez, it's turning into a nightmare effort. When the car works, which is most of the time, it works so well, and is such a blast to drive! But considering at any time if I'm rolling to a stop and then go to press the pedal nothing may happen, it's definitely not safe to drive. If anyone out there could sell me a simple tablet with simple software that would allow me to make these simple changes to the Zilla settings I would gladly pay. I've got the manual, and understand most of what I need to do, it's just getting to that point that has eluded me.

 

[piotrsko]

Try a recycling computer store for an old XP laptop. Here in Reno they can be had for $100.

 

[stevefed]

Well, I was finally able to get into the Hairball with my laptop and check all the error codes, which was really exciting, but nothing pointing to my issue, and nothing major needing adjusting as far as voltage/amp limits. This bizarre issue remains, which is that any time I completely take my foot off the pedal I may have no power the next time I try to use it again, and the only way to get it to work again is to turn the car off and then on again with the key. There doesn't seem to be any rhyme or reason to when it happens. It can happen the first time I turn on the car and go to pull out of my driveway, or it can happen when I'm tying to pull out from a stoplight/stopsign, or it can happen when I'm doing 70 on the freeway and try to accelerate after coasting. the main contactor is still connected, everything continues to work perfectly normally, except no signal is coming out of the controller to the motor. So far I have replaced all of the following without any change:
Relays for both the Keyswitch and the Potbox
Potbox, all wiring to controller from ptotbox, and a 3rd spring to make sure it is returning all way back when pedal is released
Countless hours checking all wiring, fuses, connections

This is an old Electro Automotive conversion which uses a relay to prevent the car being able to drive away if the charger is plugged in, I'm planning on going back over that. Another thought is that it's the keyswitch/ignition, which is probably original to the car, or the wiring going to it which I haven't checked yet.
Lastly, there was never a microswitch connection on the pot box hooked up to anything, although the electro automotive kit has instructions to connect it to the relay. Since this problem didn't happen when I first put batteries in, and the car had been updated to the hairball with a direct connection from the potbox, I didn't see a need for it, but maybe there needs to be a wire to bridge where the microswitch is supposed to engage the relay?

Or, maybe it's simply possessed by a demon that is enjoying making me go crazy?!

 

[EVfun]

Well, I was finally able to get into the Hairball with my laptop and check all the error codes, which was really exciting, but nothing pointing to my issue, and nothing major needing adjusting as far as voltage/amp limits. This bizarre issue remains, which is that any time I completely take my foot off the pedal I may have no power the next time I try to use it again, and the only way to get it to work again is to turn the car off and then on again with the key.

[snip]
To the one thing I clipped, no, you do not need the pot box micro switch with the Zilla controller. The Zilla has control of the contactor and would throw error codes if you used the microswitch to cut it out.

What error codes do you have after a no throttle response event? Sometimes odd codes or code combos can point to strange problems. If you have error codes that the Zilla has saved you can clear them to see what is new after an event. It would be good to try and get the codes before you shut the controller off to reset it, but obviously you have to keep yourself safe on the road first. The laptop can be plugged in while you drive the car, but don't be charging the laptop off a car charger while it is plugged into the Zilla.

Do you have the 2 wires that go to the hairball precharge terminals connected directly to the contactor power terminals? You may get some strange cut-outs if you choose electrically equivalent locations. I had to fix that wiring error on one car I installed a Zilla in, but in a prior conversion it wasn't an issue.

I would swing over to the Manzanita Micro site and grab the manual if you haven't already. The DAQ modes outlined in near the back of the manual can also be helpful for some problems.

 

[stevefed]

Hi EvFun, thanks so much for helping me out on this. It's Saturday and finally I have a little time to problem solve. I got back into the Hairball just now and checked for error codes. Since I last cleared it, and the only issue I am aware of that took place was the throttle one I described, there was also only one error message ~1124, which is "Main Contactor Stuck On" You asked about the precharge connections, which are in fact directly connected to the main contactor. I guess my question is how did you change the routing of the wiring to solve the problem you had? This seems like a good first step for me to take while I'm waiting on a hall effect pedal to arrive. I suppose, considering the main contactor came with the car it might be a good time to order one of those as well, as it's one of the few electrical components left that I have not replaced since the change to 144v. Thanks again for your help and support on this, I feel so close yet so far, and am dying to be able to use this as a reliable, safe (and fun!) ev in the near future.

 

[stevefed]

With your advice I was able to wire the laptop into the Hairball and put in in the passenger seat while going back and forth a few feet in the garage. I was able to recreate the issue at least 3 or 4 times and each time it went from the normal 1314 (waiting for throttle) to 1124 (Contactor Stuck On). I'm going to go ahead and replace the contactor, as they're not terribly expensive and I should upgrade to a sealed one anyway, but would love to hear how you rewired the power to the contactor coil from the Hairball as well. I feel like I'm getting closer here. Thanks for the help!

 

[Frank]

I was going to suggest the main contactor, sounds like you might have found it.

 

[EVfun]

Hi EvFun, thanks so much for helping me out on this. It's Saturday and finally I have a little time to problem solve. I got back into the Hairball just now and checked for error codes. Since I last cleared it, and the only issue I am aware of that took place was the throttle one I described, there was also only one error message ~1124, which is "Main Contactor Stuck On" You asked about the precharge connections, which are in fact directly connected to the main contactor. I guess my question is how did you change the routing of the wiring to solve the problem you had? This seems like a good first step for me to take while I'm waiting on a hall effect pedal to arrive. I suppose, considering the main contactor came with the car it might be a good time to order one of those as well, as it's one of the few electrical components left that I have not replaced since the change to 144v. Thanks again for your help and support on this, I feel so close yet so far, and am dying to be able to use this as a reliable, safe (and fun!) ev in the near future.

Please check your 12 volt system voltages carefully and study the car wiring for any questionable connections in the 12 volt power to the Hairball. 1124 can be a caused by a "phantom" error. That is to say, this has been known to pop up when the real problem is the 12v seen by the controller briefly dropping too low. This one seems more common with loose connections -- rapid small fluctuations in the 12 volt supply. This is a controller that got it start in racing. It is very sensitive to 12 volt issues because when passing high amps for 10+ seconds a really good contactor connection is a must.

I initially had the precharge connections to the controller side of the main contactor and the other side to the output of a pack positive fuse just 18 inches away. My system allowed me to kill all loads by pulling the small pack positive fuses (charger, DC>DC and precharge.) The first car I did this to worked fine. When I did that installation on my beach buggy I was tossing an 1141 codes and a couple others, randomly, when I touched the throttle. Wiring directly to the contactor with both precharge lines eliminated the problem. You might even want to twist those 2 wires as they run back to the Hairball (I did when moving both wires to the contactor, don't know if it was actually needed.)

I used to have problems tossing the 1224 error code when turning on the headlights because I do not have a 12 volt battery in my beach buggy (only a DC to DC converter.) I made a headlight warm-up system to deal with that, but removed it when I installed LED head lights. They draw much less current and don't have a huge current inrush when they turn on like incandescent bulbs.

 

[stevefed]

Thanks again, either way it's a good idea to replace the main contactor, but while I'm at it I will check the 12v going to the Hairball and make sure it's getting proper voltage, it sounds like it definitely needs a going over, and good be a big part of this issue. I'll let you know how it goes, summer vacation is just around the corner and lots of time to work on this project.

 

[stevefed]

OK, main contactor replaced, I really like the new solid "thunk" it makes, but unfortunately, no change in this issue, so back to the drawing board, or forum, I go. I'm still getting the same 1124 error code about main contactor stuck. I checked the 12v inputs on the Hairball with the car on. The "SLI + 14v In" reads a steady 13.6 unless I put the car in reverse and the lamps come on, where it drops to 13.4 (I guess this is probably happening when I hit the brakes and the lights come on as wel? The "Start Input" appears to read a steady 13.6. The "key input" however seems a bit weird as it fluctuates between 12-12.4, could that be it? Again, this is with the car sitting in the driveway on and me touching a meter to each of the screws that go with these terminals on the Hairball. Any thoughts? I'm really starting to run out of ideas, but feel it has to be something to do with the 12v system. My dc-dc converter is brand new and appears to be working perfectly, I've replaced the relays and tracked down wires and connections where things seem like they're right, but I guess I'm missing something, or could this be related to something in the ignition switch of the car? Any help most greatly appreciated.

 

[EVfun]

If the key input is fluctuating while nothing else is happening that is likely the problem. My understanding is that the start input and SLI input are not used for major functions, those are handled by the key input so the vehicle operator maintains the final veto power. I would suggest turning the car off and "pull testing" the wiring a bit. If you grab a wire near a connector and give it a gentle wiggle and tug the wire should not pull out and the terminal should not come off. Those that do where already bad. It is time to check this path from the battery to the Hairball.

...or a work around could be to lay in a new set of temporary testing wires, battery + to fuse to toggle switch inside of car to Hairball key input and start input. Disconnect the current connections to those 2 terminals and keep the wires ends out of they way so they don't short out. It is a more complete test of the "ignition" wiring system by elimination.

 

[stevefed]

Thanks so much EVFun. I've been taking a short break to walk away from it, but taking your advice will now get back to it to see if it will solve this riddling issue. Thanks again!

 

[stevefed]

I think that was it! I rewired the key input from the original wiring to/from the relay and used different connectors and also moved the connection for the water pump on the cooling system and all is working perfect, thank you so much EVFun for you patience and willingness to help me out on this! If anything goes wrong I'll let you know, but for now it's time to start seeing what kind of range I can get out of it. Yea!

 

[grizzliz]

You say you were finally able to connect your hairball to you laptop; I can't for the life of me get this to work. I've got a converter cable with a FTDI chipset to go from the USB of my laptop to a db9 connector. On the hairball side, I've got a rj12 that fits into the port on the hairball, and I'm inserting the 3 necessary wires into the db9 connector. Can't get anything to appear on my laptop. Any advice would be greatly appreciated.

 

[Frank]

You need to run a terminal emulator program with proper baud rate and other comm parameters set. Assuming you're doing this, which emulator are you using?

 

[grizzliz]

I've used coolterm, PuTTy, quickterm, exterm (I think those are all of them.) I bought the Zilla 2k on ebay, and I'm not even sure the hairball is functional, although I've opened it up and nothing looks burnt. I'm using the rj11 diagram in the zilla manual, and I'm just using what looks like the Tx, Rx, and ground wires. I've tried a cable with the prolific ps-2303 chipset and the FTDI chipset. If I check the 3 wires from the hairball for power, only the Tx wire shows power (negative 10v approx.) I've got 12 volts going to the SLI connection, and it's grounded to the chassis.