car is a 95 cx with a 97 gsr running a chipped p28, chipping by me, when i goto start the car it idles a little high a has a cel, so i jump the plug and turn the key to the "on" postion and it doesnt even blink, stays solid, i read that means my ecu is fried but my starts and idles and revs fine, whats with that cel? because i have another p28,untouched, and theres cel when that ones pluggled in. also the cruise control light comes on? no idea how that got there

 

up

 

ECU malfunction but running should throw a P1607 code... I've never heard about the Cruise control thing. Mine throws a 1607 due to having the immobilizer removed, but runs 100% fine.

Scan the code and post what it says. I don't know very much about chipping at all, but pulling the code is ALWAYS the first step.

 

It's possible that the ECU is fine and that you instead have a short in the service connector or CEL circuit.

 

the car is obd1 so i cant "scan" for codes, i see what your saying about the service conntecor, but when i jump it, the srs light blinks, indictaing that its been jumped correctly right?

 

The SRS blinking suggests no short in the service connector wire. Now check for a short in the CEL wires.

 

if there was a short in the cel wires would i always have a solid cel? or would i only have a sloid when the service connetor is jumped?

 

becasue the ecu i use to run the car (untouched p28) doesnt throw any codes

 

Check for a short in the Grn/Orn wire running between the CEL and ECU. A short in this wire would cause the CEL to stay on. If this wire is fine, swap in a known good ECU.

 

A couple things come to mind.

On the ECU, here are some possible things that would give you a solid CEL (since you say the other P28 does NOT give you a CEL):
1. You forgot to remove the checksum routine.
2. Something is wrong with the flash on the chip.
3. You have a cold solder joint or a solder bridge somewhere. Maybe pulled trace if you have not desoldered/soldered many ECU's.
4. You have a ZIF plugged into the soldered in socket and one of the pins on the ZIF is bent or it's not making good contact.

SCS connector not working on ECU (ECU not responding to jumpered service check connector). It's obvious that the SCS connector itself is working if you are getting a flashing SRS light. If you cut the jumper in the ECU for datalogging, SOME ECU's (not all) will no longer let you check codes through the connector in the passenger kick panel.

So, I'd pull the chip out of your ECU, read it, make sure the checksum routine is removed, then reflash. Make sure you are using a P28/P30 base file since the P72 base file has maps that are different resolution (less cells on the P72 tables).

Other thing I can think of is maybe the jumper wire accidentally got left in; that can cause a solid CEL...

 

Actually, the SRS light should not blink when the service connector is jumped. For the 5th gen Civics, CEL and ABS codes, not SRS faults, are retrieved by jumping this connector.

 

well i bought the chip form xerocron, with a p72 basemap, so i would hope they would remove the checksum, now what do you mean as a soder brige? like a joint touching more things than it should?

 

Yes, a solder bridge is when you have solder touching your intended connection and another spot (trace, adjacent joint, etc). If you have a removable jumper, remove it and see if the engine light goes away; this will put the ecu on the basemap built into it.

Is the P72 basemap for a P72 ECU or P28? I'm pretty sure you have to use the correct ecu base since the map resolution is different between the 2.

 

Ryan, don't you think the OP has wiring issues that must be fixed before worrying about the ECU. For example, from what I can gather, the cc light and SRS turn on/blink with the service connector jumped (not even close to normal) and the CEL remains on steady with and without the service connector jumped yet the engine runs. I think some wires have been swapped or are shorted.

 

Yes, I'm sure there are more problems with the car. However, he stated that the CEL went off with a different P28 so I think that there is also a problem with his chipped P28. Sounds like a clutster F#(% to me so the problems just need to be crossed off the list as they are resolved. LOL.

 

Multiple problems are likely. As you can see in his original post, the chipped ECU gives a solid CEL (=CEL code 0) whereas the P28 gives some unspecified CEL codes. I am not sure if the chipped ECU is bad or simply programmed to report differently than the P28 ECU.

OP: What CEL code does the P28 ECU throw? Does the SRS light and cc light also blink/turn on when the P28 is installed and the service connector is jumped?

 

ok hopefully this will hep..
- ihave 2 p28s, p28* is untouched and p28# is chipped with a xercron chip that i oreder and socketed in
-with p28* the car runs good no cel nothing idles great doesnt sputter at all and the cc light IS NOT on
-with p28# it throws a cel and the cc light is on, so when i go to seee what codes its trowing, it shows a solid cel, the srs blinks and the cc light remians on
hopefully that clears some stuff up

 

As Ryan previously said, the problem is that P28# is bad.

 

when i ordered the chip from xerocron i stated that i wanted a p72 basemap and it was going into a p28

 

I'd email them just to make sure they put a P28/P30 based file in your chip. Honestly, I think you should double check the soldering in the ECU. Having things on that should not be when you swap only the ECU makes me suspect solder bridges, pulled traces, or something else bad in the ECU. Open it up and double check. You can also remove or cut J1 on the board of the ECU. I put removable tabs in mine so you can easily revert to the stock map in the ECU. Once that is cut, see if the problems go away. I doubt they all will but that will probably get rid of your solid CEL. You are putting the ECU back into stock mode where it uses another chip on the ECU board to run the engine; just like stock.