No Connection To ECU???????
09-21-2009, 10:39 AM
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No Connection To ECU???????
i am tuning with crome pro and i cant get the laptop to connect it has connected before and now it wont i have tried 2 ecu's all new hardware different laptop. its really pissing me off just no connection. i want to try more stuff i just need to know were to start. please let me know. you can text me too at 208-954-2565 my name is Rich thanks guys i havent been able to drive the car for 8 months cause of this so any help is awsome
09-21-2009, 01:43 PM
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Re: No Connection To ECU???????
What kind of hardware are you using? What ECU are you using? ODB0 - I - II?
If you have ODBI, and are using a serial device like Hulog or Hondalog, don't forget to remove J12. This 'jumper' will allow you to log serially...
If you have ODBI, and are using a serial device like Hulog or Hondalog, don't forget to remove J12. This 'jumper' will allow you to log serially...
09-21-2009, 01:46 PM
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Re: No Connection To ECU???????
wow now that is trust to give your number out on h-t lol. either that or you're mike jones!
as for your problem, it may sound stupid but open up the ECU and see if the chip got knocked loose, it's happened to many people before.
as for your problem, it may sound stupid but open up the ECU and see if the chip got knocked loose, it's happened to many people before.
09-21-2009, 03:28 PM
#4
Re: No Connection To ECU???????
Well, If you say that you have used multiple ECU's (presumably both known working) and multiple laptops (presumably with working COM/USB ports).
Useful information to help us help you troubleshoot the problem such as: 1) OBD version, 2) ECU type (P28, 72, ect.), 3) JDM or USDM, 4) Interconnecting methods (Hulog, DLC, etc) 5) Define undriveable (does it even start or does it run too poorly to drive?) 6) Did you change anything before this problem occurred? (such as laptop operating system, fuel injectors, etc) 7) ... ?
If you have access to an oscilloscope, then check the intermediate outputs between your computer interface and the ecu in question. (i.e. start closest to you computer. Check to see if you have any signals through your USB/Serial/DLC cable). If there is *check* (likely computer driver issue, setting issue such as baud rate, bit characteristics like stop/parity, etc.)
If there isn't any signal, then move closer to the ecu (i.e. on the other side of your Hulog or Hondalog or cable interconnect. Check (preferably from inside your ecu directly from you stripline) if there is any communications 'leaving' the ecu. If there is *check*. (likely the connecting instrument between the ecu and computer such as hulog kit device, misplaced wires, broken connections, etc)
If there isn't, then there is likely to be a problem with the ecu (such as solder job, floating short (such as a small shard inside the ecu caused by drilling the hole for the comm wires)), etc. Thoroughly inspect the PCB for abnormal parts.
I would go on but I have to leave at the moment. If anyone sees problems, don't hesitate to correct/add.
Hope this helps
Useful information to help us help you troubleshoot the problem such as: 1) OBD version, 2) ECU type (P28, 72, ect.), 3) JDM or USDM, 4) Interconnecting methods (Hulog, DLC, etc) 5) Define undriveable (does it even start or does it run too poorly to drive?) 6) Did you change anything before this problem occurred? (such as laptop operating system, fuel injectors, etc) 7) ... ?
If you have access to an oscilloscope, then check the intermediate outputs between your computer interface and the ecu in question. (i.e. start closest to you computer. Check to see if you have any signals through your USB/Serial/DLC cable). If there is *check* (likely computer driver issue, setting issue such as baud rate, bit characteristics like stop/parity, etc.)
If there isn't any signal, then move closer to the ecu (i.e. on the other side of your Hulog or Hondalog or cable interconnect. Check (preferably from inside your ecu directly from you stripline) if there is any communications 'leaving' the ecu. If there is *check*. (likely the connecting instrument between the ecu and computer such as hulog kit device, misplaced wires, broken connections, etc)
If there isn't, then there is likely to be a problem with the ecu (such as solder job, floating short (such as a small shard inside the ecu caused by drilling the hole for the comm wires)), etc. Thoroughly inspect the PCB for abnormal parts.
I would go on but I have to leave at the moment. If anyone sees problems, don't hesitate to correct/add.
Hope this helps
09-23-2009, 10:37 AM
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Re: No Connection To ECU???????
Its a 92 honda civic B20 vtec, the ecu is a p28 OBD1. Well first i was able to connect to the ecu and change everything and everything worked fine, but now out of a sudden changes i made wouldn't save. I figured it was a software issue or a virus on the laptop so i did a system restore to see if that would help but now it wont even connect to the ecu. I undid system restore but it still doen't connect.
09-23-2009, 12:49 PM
#6
Re: No Connection To ECU???????
Are to trying to modify the ECU settings via a real-time-programmer (RTP)? or are you re-chipping each time you have written a change in code (via what? Chrome, Uberdata, Hondata, eCtune, etc)
To my knowledge (without special circuitry and depending on the chip-job) you can't reprogram the eprom while it is inside the ecu. There is no way to reprogram an eprom without hitting the 'program' (VPP, pin 1) pin with less than 10v. Unless that circuitry is there, your not changing the values. Its also possible that your output enable is held high for some reason (short, floating open due to bad socket).
To once and for all check to see if your ecu works at all, cut the external memory jumper (J1) and see if your car starts and runs at all. This will run your stock OEM P28 setup. You should only do this if your naturally aspirated and it is safe for your engine (you decide because you know your modifications). If it does, you have a problem with your chipping / socket parts.
What I would try is writing an entirely new prom (outside of ecu) and re-chipping. at27c256 chips are $2.80 each at digikey. (after reinstalling the J1 jumper)
Reinstall your software, check your COM ports in device manager (assuming your using windows). If you see any question marks or exclamation points, somethings wrong there.
Any additions or corrections are welcome. Good hunting.
Edit: Oh, not all 27256's are rewritable/changeable. Some are eraseable (via UV light), most are OTP (one time programmable).
To my knowledge (without special circuitry and depending on the chip-job) you can't reprogram the eprom while it is inside the ecu. There is no way to reprogram an eprom without hitting the 'program' (VPP, pin 1) pin with less than 10v. Unless that circuitry is there, your not changing the values. Its also possible that your output enable is held high for some reason (short, floating open due to bad socket).
To once and for all check to see if your ecu works at all, cut the external memory jumper (J1) and see if your car starts and runs at all. This will run your stock OEM P28 setup. You should only do this if your naturally aspirated and it is safe for your engine (you decide because you know your modifications). If it does, you have a problem with your chipping / socket parts.
What I would try is writing an entirely new prom (outside of ecu) and re-chipping. at27c256 chips are $2.80 each at digikey. (after reinstalling the J1 jumper)
Reinstall your software, check your COM ports in device manager (assuming your using windows). If you see any question marks or exclamation points, somethings wrong there.
Any additions or corrections are welcome. Good hunting.
Edit: Oh, not all 27256's are rewritable/changeable. Some are eraseable (via UV light), most are OTP (one time programmable).
09-25-2009, 07:02 AM
#7
Re: No Connection To ECU???????
I have just found a simple program (obviously visual basic) that will test TTL to USB device communications
http://www.moates.net/zips/aldltest-full.zip
If you short pins 2 and 4 of your TTL side connection, this program will test your device your using for communicating with the ECU. The downside of the program is... it won't test the specific baud rate honda ecus are using, i.e. 38.2kbps
Nifty though.
http://www.moates.net/zips/aldltest-full.zip
If you short pins 2 and 4 of your TTL side connection, this program will test your device your using for communicating with the ECU. The downside of the program is... it won't test the specific baud rate honda ecus are using, i.e. 38.2kbps
Nifty though.
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