Anyone can tell me where the ELD(load detector for the alternator) is located in a EK civic? I heard that it is in the fuse box for EG civics but what about EKs?

 

Should also be inside the underhood fusebox on an EK. The problem is that it's part of the actual fuse box. You cannot disassemble it or anything. The fusebox should have a 3 pin connector for the ELD, but thats it. If you need to replace the actual ELD, you have to replace the whole fusebox...

 

What can a faulty ELD cause? Can it cause hesitation on drive during steady throttle state?

 

The only thing that sensor is for, is so the ECU can tell the Alternator to switch into low-charge mode. That means the alternator drops it's output to the 12.x volt range, and spins easier. This should only happen during idle & light throttle acceleration (up to about 40mph), with all accessories & lights off...

The only symptom of a bad ELD listed in my CRX manual is "idle too low when warm", so I don't know what to tell you. I also know it's a code 20 on the MIL...

 

I see corrosion at my battery negative terminal. Is that a sign of something wrong with my ELD? I have a PowerFC unit and the ELD voltage reads 3.35V which is different from my friend's car of 4.5V. He has a PowerFC too. This reading is at idle. How much will that fuse box cost me?

 

Look on ebay for a used one. They are dirt cheap. The ELD unit doesn't actually connect to the battery wires at all. Corrosion is from poor grounds on the chassis & motor (or bad battery cables)...

Also, the ELD isn't supposed to output a fixed voltage. The voltage drops as accesories & lights are turned on. This is how the ECU detects the vehicles "electrical load". Here are typical voltages for 91 CRX (yours should be the same):

Ignition "on" (not running) = 4.5v - 5v
Parking lights on = 2.5v - 3.5v
Headlights on = 1.5v - 2.5v

It is possible it is working correctly, but the ECU isn't getting the signal. In that case, you would get a code 20. Check for opens, or shorts in the wires...