Honda ELD Bypass: Things You May Do to Get Rid of the Problem

Honda may have had a noble intention when it decided to install ELD (Electrical Load Detector) in its vehicles back in the day. This piece of equipment serves to mainly ensure fuel economy by regulating some of the vital functions of the car in some conditions. However, many of its vehicle owners have found that part to be quite troublesome in the long run and have resorted to bypassing it.

ELD problems highlights

• Level of urgency:medium
• DIY inspection:impossible
• DIY repairs:impossible
• Can you drive?yes
• Price of repairs:$300 - $450
• If ignored:poor alternator work, power anomalies, glitches
• Ways to fix:find a good mechanic for inspection and repairs

What is ELD and How Does It Work?

Since the 90s Honda vehicles have been equipped with an ELD unit in the fuse or relay box under the hood. This device sends varying voltage signals to the PCM (Powertrain Control Module) based on the amperage load readings that it gathers from the battery. Basically, it is considered to be a mini current transformer for its cars.

From there, this piece of tech monitors the amperage requirements of the vehicle to help the PCM control the electrical field signal going to the alternator. This, in turn, boosts the power delivery of the alternator.

The ELD is located in the fuse box under the hood just beside the battery. It features a three-wire configuration composed of the primary voltage lead, primary ground, and a load output lead. The last wire is the one utilized by the PCM as a reference in determining the signals it sends to the alternator. It should be noted that in this setup, the PCM is linked to the alternator rather than the ELD.

The ELD system was ultimately designed to improve fuel economy and emissions in Honda vehicles by regulating the load on the engine at specific conditions. The factors involved vary depending on the vehicle application but these normally take into account the engine rotational speed, vehicle speed, electrical load, coolant temperature, air intake temperature, and operation of the air conditioning system.

Issues with the Honda ELD

The ELD has the potential to cause problems as the vehicle ages. The most common symptom of a failing or faulty ELD is dimming headlights or interior lights. This is because the alternator is not receiving the correct voltage signal from the PCM and as a result, is not providing enough power to run all of the electrical components in the vehicle.

Other electrical issues that can arise from a faulty ELD include issues in the power windows, locks, and seats. In addition, the stereo system may malfunction or completely shut off. The check engine light may also come on as a result of the alternator not receiving the correct voltage signals.

A failing ELD can ultimately lead to a dead battery if left unchecked. This is because the alternator is not providing enough power to recharge the battery while the vehicle is running. As a result, it will eventually run out of juice and leave you stranded.

Replacing a failing ELD is rather simple and can be done by any qualified mechanic or technician. All you need is a new ELD unit and the proper wiring harness for your specific vehicle. But then again, there are some models of Honda that had the part designed to be packaged with the entire fusebox. That means you will have to purchase the fusebox to get access to a new ELD component. Now, that's an extra cost on your part. Therefore, a good way to go with this is by resorting to aftermarket parts.

Furthermore, by design, the ELD has sometimes proven itself to be unreliable that's why many people resort to bypassing it. This can be done using various methods.

Good Reasons to Bypass the ELD in Honda Cars

The most common reason why people bypass the component in their Honda cars is to improve fuel economy when their stock ELD is already failing to do its job properly. The most common method is by installing a resistor in line with the primary voltage lead going to the PCM.

By doing this, the PCM is forced to reduce the voltage it sends to the alternator. As a result, the alternator will not work as hard and will tap less power from the engine.

The other good reasons to bypass the ELD according to sources include:

• Bypassing the ELD can increase engine power because the alternator will not have to work as hard.
• If your ELD is failing or malfunctioning, bypassing it can prevent electrical issues from arising.
• Bypassing the ELD can reduce emissions because the engine will not have to work as hard to power the alternator.
• If your ELD is failing or malfunctioning, bypassing it can save you money on repairs.
• If your ELD is failing or malfunctioning, bypassing it can prevent your battery from dying.

As you can see, there are many good reasons to bypass the ELD in your Honda. However, it is important to note that bypassing the ELD can void your warranty so be sure to check with your dealer first and think about your decision carefully before proceeding.

Ways to Bypass the ELD in Honda Cars

Rummaging through forums and personally asking some mechanics about the matter, here are the most common methods employed to bypass the ELD in Honda cars:

1. Using a resistor

Installing a resistor in line with the primary voltage lead going to the PCM is the most common way to bypass the ELD in Honda cars.

2. Using a capacitor

Another way to bypass the ELD in your Honda is to install a capacitor in line with the primary voltage lead going to the PCM.

3. Using an inductor

Yet another way to bypass the ELD in your Honda is to install an inductor in line with the primary voltage lead going to the PCM.

4. Using a diode

Finally, you can also bypass the ELD in your Honda by installing a diode in line with the primary voltage lead going to the PCM.

Which method you use to bypass the ELD in your Honda is up to you. However, we recommend using a resistor as it is the simplest and most effective way to do so.

Installing a Resistor to Bypass the ELD in Your Honda

• Locate the primary voltage lead going to the PCM

The first step is to locate the primary voltage lead going to the PCM. This can be found by tracing the wires from the alternator back to the PCM.

• Cut the wire

Once you have located the primary voltage lead, cut it with a pair of wire cutters.

• Strip the ends of the wire

Next, strip the ends of the wire using a wire stripper.

• Attach the resistor

Finally, attach the resistor to the ends of the wire using solder or crimp connectors.

• Reconnect the battery

Once you have installed the resistor, reconnect the battery and start the engine. The engine should run normally and your fuel economy should improve.

It is important to note that you may need to experiment with different values of resistors to find the one that works best for your specific Honda car. We recommend starting with a 10-ohm resistor and increasing or decreasing the value as needed.

Installing a Capacitor to Bypass the ELD in Your Honda

Simply repeat the whole process shown in the previous item of this list leading to the fourth part, but instead of attaching the resistor to the ends of the wire, use a capacitor. End by reconnecting the battery and starting your engine to test whether or not the bypass worked.

Again, you may experiment with different values of capacitors to find the one that works best for your specific Honda car. We recommend starting with a 10 uF capacitor and increasing or decreasing the value as needed.

Installing an Inductor to Bypass the ELD in Your Honda

Same as the previous item, repeat the entire step until you get to the fourth part wherein you have to use an inductor instead. Finish by reconnecting the battery and testing what you've done by restarting the engine.

Feel free to experiment with different values of inductors to find the one that works best for your specific Honda car. We recommend starting with a 10 mH inductor and increasing or decreasing the value as needed.

Installing a Diode to Bypass the ELD in Your Honda

Similar to the previous items, replicate the steps until you get to the fourth part wherein you will have to install a diode in its place. Lastly, reconnect the battery and start your engine to get a feel of your successful auto surgery.

Likewise, it is worth noting that you may need to experiment with different values of diodes to find the one that works best for your specific Honda car. We recommend starting with a 1N4001 diode and increasing or decreasing the value as needed.

Conclusion

After going through these, we hope that you will be able to weigh your options between bypassing your problematic ELD or simply finding a replacement for it. Should you ever decide to go through with the bypass, be sure to keep in mind the methods shown to you here, and when in doubt, always consult your mechanic.