P1298 ELD High Input...... ???

[slayer1219]

1997 civic LSV (b18b1/b18c1).... Need some help from some of the mechanics that are on here... I have a p1298 code that I cant get rid of. The ELD, along with the whole under hood fuse box, is brand new. Every fuse in the car is good too (including that stupid #15) . I use a p75 ecu only when it comes time for inspection so between last year and about a month ago the p1298 code popped up. I even had Honda of Hickory take a look at it and the technicians pretty much had no idea. I switched ecu's to determine whether or not the p75 was faulty but, that p1298 code still showed up.

The only other thing I can think of that could be affecting the ELD is the HID's I installed about 6wks ago.
Im gonna buy some stock bulbs later on and see if that helps.

Could the HID's be too much load? Would tha make the ELD say its receiving a "High Input".

If not then,

I'm just wondering if any of you guys had an experience like this and what was done towards fixing it.

 

[Szady]

I know Xpl0d3r had that issue on his 97 EK with a boosted JDM B18b. We could never figure out where it came from, though. He too, has HID's. I never had that CEL for the 6 years I had my 00 EK sedan, even with a B18b1 swap. I know though, that it didnt affect anything on the car. Lights still all worked, etc. Maybe he'll chime in and respond...

 

[XpL0d3r]

Even though, Fuse 15 is good, I'd still take a look at this: http://www.tegger.com/hondafaq/tsb/civic/x99-029e.pdf to verify that there's no wiring issues.

I did a lot of research on that damn code, even replaced the ELD on mine had the same issues. For me, it ended up being a faulty MAP sensor. It took the tuner a couple days to find, after checking basically the entire wiring system, and even replacing the wire harness! Check all your wiring as well, and clean your grounds to ensure the best contact.

 

[slayer1219]

thank you, looks like I have a full weekend ahead of me

 

[slayer1219]

well... the map sensor checked out fine. I tried a new one just for giggles and the code just popped up again like before. I failed to mention in my original post that the scan tool is also picking up p0141 along with the p1298.

 

[RonJ]

The MAP sensor has noting to do with the ELD circuit, so it's unclear to me how it could possibly be related to code P1298.

OP - Try unplugging the secondary O2 sensor to see whether P1298 is eliminated.

 

[slayer1219]

I am not very good with electrical work. When I first had those codes pop up the first thing I did was take a look at my secondary O2. I found that the O2 pig tail was cut. (Out of the two shops that work on my car I am not sure who did it). I bought a new secondary O2 and had to buy an extension for it to reach. Still have the same codes. Im guessing the wiring coming from my car is at fault. With the help of my repair manual, Im going to check the heater circuit. Is there anything else I should be doing?

 

[RonJ]

Post pictures of the 2nd O2 sensor heater wire splices. Did you solder and heater shrink insulate those junctions?

Did you unplug the secondary O2 sensor to see whether P1298 is eliminated?

 

[slayer1219]

Hope i did this right...

This is my secondary O2 w/ the extension looking from the rear of the vehicle towards the front


http://imageshack.us/a/img153/3228/tlu6.jpg


Close up of the same O2 sensor extension

http://imageshack.us/a/img812/3470/3yac.jpg


With the engine off/ Ignition on this the Heater Power voltage (12.0)

http://imageshack.us/a/img189/5536/sa9y.jpg


Back probing with the engine on and at operating temperature this is the Signal output (0.2)

http://imageshack.us/a/img546/2493/zx02.jpg

back probing with the engine on and at operating temperature this is the Heater output (0.4)

http://imageshack.us/a/img593/6420/4qae.jpg

 

[slayer1219]

sorry for the crappy pictures. Its tough to hold everything and take a picture. DId I have the VOMeter on the correct settings?

and to make my morning better I'm leaking antifreeze now

 

[RonJ]

Did you unplug the secondary O2 sensor to see whether P1298 is eliminated?

 

[RonJ]

This is my secondary O2 w/ the extension looking from the rear of the vehicle towards the front


http://imageshack.us/a/img153/3228/tlu6.jpg


Close up of the same O2 sensor extension

http://imageshack.us/a/img812/3470/3yac.jpg


With the engine off/ Ignition on this the Heater Power voltage (12.0)

http://imageshack.us/a/img189/5536/sa9y.jpg


Back probing with the engine on and at operating temperature this is the Signal output (0.2)

http://imageshack.us/a/img546/2493/zx02.jpg

back probing with the engine on and at operating temperature this is the Heater output (0.4)

http://imageshack.us/a/img593/6420/4qae.jpg

There's not much helpful to diagnosis here^.

1) The pictures don't allow anybody to very that the two heater wires are pinned correctly to fuse 15 and the ECU.

2) You don't mention or show which O2 sensor wire reads 12 V (battery voltage) to body ground. And, in general, set you multimeter to DCV 20, not DCV 200, for voltage measurements of your car.

3) P0141 has nothing to do with the O2 sensor signal, only the O2 sensor heater element.

 

[slayer1219]

From my understanding p0141 means that the heater circuit is not working properly

The heater power (hpwr) is the one reading 12v.... But that doesn't matter I guess...

What your saying is the next thing I should check is if the heater circuit is pinned correctly to fuse 15? Do I need to probe that too? Any specific voltage that it needs to read?

 

[RonJ]

From my understanding p0141 means that the heater circuit is not working properly

Exactly. The relevance being that the heater element and the ELD circuits both get voltage via fuse 15, hence a possible connection to P1298.

The heater power (hpwr) is the one reading 12v.... But that doesn't matter I guess...

This is insufficient information because you haven't told us whether this voltage wire is properly pinned to the O2 sensor. In other words, is the voltage delivered to the right place?

What your saying is the next thing I should check is if the heater circuit is pinned correctly to fuse 15?

What pin in the O2 sensor connector gets this voltage?

...and...

Is the heater element ground wire properly pinned to the ECU.

Download the 96-00 Civic service manual to obtain troubleshooting instructions and circuit diagrams for both the ELD and heater element CEL codes.

 

[slayer1219]

And about unplugging the o2 sensor.... The code was on when the wires were cut on the old o2, I replaced that o2 sensor with a new one and added the extension. The same codes popped up.

 

[slayer1219]

Ok, ill have to double check the pin that was reading that 12v. Ill check the ecu for that ground. I could have caused a bad connection by having to unplug and plug different Ecu's

 

[RonJ]

Ok, ill have to double check the pin that was reading that 12v. Ill check the ecu for that ground. I could have caused a bad connection by having to unplug and plug different Ecu's

And get the service manual.

 

[RonJ]

And about unplugging the o2 sensor.... The code was on when the wires were cut on the old o2, I replaced that o2 sensor with a new one and added the extension. The same codes popped up.

Did you reset the ECU and both codes returned?

 

[slayer1219]

Ill double check which pin is getting that 12v. Ill check my ecu for that ground, it could have wiggled loose when I was unplugging and plugging the different Ecu's.... I appreciate all the help, by the way... I hope I'm not sounding like I'm not

 

[RonJ]

Click site 1 in my signature.