This 2001 Honda Civic came in with a multitude of problems one of which was a code P1298 stored for an ELD fault (electric load detector circuit input high). I had never had to actually test one of these before although I knew that they existed. The ELD sends a signal to the engine control computer so that the computer can adjust the alternator output in relation to power consumption. The ELD is located in the underhood fuse box. I am pointing to it with my screw driver.
To test the ELD I had to lift the underhood fuse box and remove the bottom cover. Once removed I could access the wiring for the ELD. The wire on the far right of the connector is power supply (battery voltage).
The wire in the middle of the connector is battery ground.
The wire on the far left of the connector is a five volt signal sent from the computer. The ELD will pull the voltage lower with increased system load and should vary with a change in load. For example if the blower or headlights are turned on it should drop. This particular unit was stuck at 3.81 volts and would not change with no loads or full loads applied. If the voltage had been near zero I would have had to unplug the connector and see if the five volt reference signal was being sent by the computer and wiring.
After testing and finding a faulty ELD, it was very easy to change. I removed the four adjoining phillips headed screws that held the two PAL fuses in place.
I released the latch on the harness connector and unplugged the connector.
With the wiring removed I simply lifted the unit. Slid the bar out and installed the new unit.
Below are a couple of pictures of the actual ELD part from Honda.
Thank You for the response Sparky, it greatly appreciated.
In response to my entry on Sun Feb 17, 09:57:00 AM 2013
1990 Honda Accord
If anyone is having same symptoms as mine try checking the 80a Battery Fuse (location – under hood fuse box). After replacing no more battery light for me.
My 80a fuse wasn’t your typical blown fuse with the breakage in the middle. It was still intact but the sides of the the copper area looked burnt. At first glance it looked good but after taking a second look with a bright light you can see the burnt sides.
Make sure to remove negative battery cable before removing the 80a fuse.
Although nothing seems impossible anymore in the world of automotive electronics, I think the real issue is with the oxygen sensor internal heater circuit and wiring. Not the actual vehicle heater system. I understand that the drive ability complaint is now gone. Have you checked and confirmed that the P1298 code has not come back as well?
Hi Sparky,
Just wanted to follow up on the issue I had with loss of engine power but no SES light coupled with the P1298 ELD Fault – after some discussions, you finally suggested to replace the front oxygen sensor. Well, I’m happy to report that, after some weeks of testing to be sure, that seems to have done the trick! Apparently when the oxygen sensor was being affected by power going to the heater, causing this result, so if you see this in person or anyone else has this problem, that’s something to check. It certainly wasn’t obvious, but after this was confirmed, my wife indicated that, in retrospect, the problem did tend to coincide with using the heater. Very interesting. Anyway, thanks so much for the assist! It was a real help in tracking this down.
-DS
The light is controlled by the alternator. You have one of three likely things happening. Fuse #15 is blown and there is an intermittent short on the wiring harness, the brushes are sticking or the belt is loose.
Will replacing the ELD fix the battery light from coming on?
Battery light comes on when pressing on brake pedal and also comes on when headlights are on. Headlights also go dim when I roll down/up windows. RPM drop for a second during all these times as well.
Battery light will also come on at high RPM for a second.
These symptoms happen randomly though…sometimes yes and sometimes no.
One day someone cut me off in traffic and had to break hard and battery light stopped coming on for days after that. I found that if break hard enough battery light won’t come on for few days.
1990 Honda Accord
New altenator, new battery, clean/solid battery connection have been done.