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How to Bypass Main Relay Honda Civic?

How to Bypass Main Relay Honda Civic?

The automotive experts are against bypassing the main relay on Honda Civic models. But, people use alternative ways to provide electric power to fuel injectors, ignition, and engine. 

How to Bypass Main Relay Honda Civic? You can bypass the main relay (ASD) by accessing it near the battery or power module under its hood, removing the wire connectors, cutting off the insulation up to 1.5 inches, attaching jumper wires to the positive and negative terminals of the relay, securing ends with tape wrapping, running the engine, and fixing the switch. You can bypass the fuel pump relay by a three-jumper wire, engage parking gears, cut off the electric supply, remove the battery, adjust the brown and blue cords with 40 and 50-pin connectors, solder them, fix the jumper cord with a tie knot, and fix the fuel pump with screws. 

Read the car’s manual to locate the tiny electric components on your vehicle. Different cords and connectors can bypass the original switch, but the circuit board lacks the standard work efficiency. 

What is the main relay on Honda Civic?

A Honda Civic main relay is an electrically empowered device that controls and regulates the electric flow. It is a tiny device with built-in connectors and terminals to attach the electric wires. 

It gives electric power to the vehicle’s electric control unit (ECU). The steering wheel sends input signals to the main switch that shifts to a new position. 

By shifting, the driver can start the car and supply the current to all appliances. The manufacturing companies make these box shape components in green, brown, and red colors. 

What does the main relay do on a Honda Civic?

It provides electric energy to the electronic features and appliances for the car. It ensures the constant electric supply to the computer system of the engine. 

It is usually present under the hood of a vehicle. It has a fuel pump switch and locates in the relay box. However, constant high heat dissipation causes long-term damage to the engine.

It can open and close the fuel and ignition systems of a vehicle. It controls the fuel pump and facilitates electric power in the fuel injectors. 

How to bypass the Main Relay (Automatic shutdown relay) on a Honda Civic?

This feature protects the motor cranking with stabilized voltage flow and prevents the car from starting without ignition. 

Bypass it with the following method, but its replacement is advisable for better results. 

Access the relay

Find the automatic shutdown switch on your Honda Civic because its location varies according to the make and model of the vehicle.

Primarily, it locates near the battery. You can find it on the side of the power module under its hood or power distribution center. 

Remove the switches

Access the wiring connectors and electric wires on the engine. Then, hold them manually, rotate counterclockwise, and remove the object.

Loosen all the mounting screws with an appropriate-sized screwdriver and lift them with your hands.

Prepare cables

Use a sharp blade, cut off the cable ends and expose the bare ends on both sides of the cords. Next, remove the insulation and access 1 to 1.5 inches of end. 

Wire cutters can strip the protective covering within a few seconds. Next, prepare the cords for further connections and keep the metal away. 

Attach the jumper wire

Purchase a simple jumper cable and attach its end to the automatic shutdown relay’s positive and negative sides. Cover the sides, secure the terminals and check the connections. 

Wrap electric tape around the connecting points and prevent disengagement. Keep both ends away from each other and maintain them in opposite directions.

Then, connect the end of the second cord to the negative and positive sides of an ASD and secure its terminals. 

Run the engine

Start its engine and run it for 10 to 15 minutes. Then, power off the electric motor and allow it to cool down. 

Adjust screws

Access the screws and remove them with a ratchet. Next, access its terminals and secure all the electric connections before the next step. 

Unscrew the ends of each cord, wrap them with electrical tape, and secure the sides. 

Check the performance 

Readjust the removed parts, connect the terminals, check the wrapping, and test drive the vehicle. Then, you can bypass the ASD without damaging the electric circuit of your car. 

How to bypass a relay with a multimeter?

You can use a multimeter to bypass a really on your Honda Civic. For this purpose, locate the switch underneath the steering column of your vehicle.

Also, its location changes according to the vehicle’s design and built-in features. Then, disconnect one electric wire from each terminal of the switch. 

Stop the electric flow and control the voltage. First, remove the caps of these cords and separate the connected wires. Then, use a multimeter and adjust it at alternating current voltage mode.

The ACV measures the volts across the terminals of a switch. The contacts remain closed with a voltage of 12 volts. However, you can find open contacts with no current.

Closed relays indicate the working conditions of a vehicle’s security system. To activate the contacts manually, use an electric cable. 

How to bypass the fuel pump relay on a Honda Civic?

The fuel pump relay supplies electric voltage to the fuel pump and engine. Therefore, it causes safety issues, and you can bypass it by the following method.

Purchase a three-jumper wire

A three-jumper wire is an electric cord with connecting pins at its ends. They can join two or more points in one electric circuit without modifying the built-in settings.

Individual wires are around 6 inches long with three JST connectors with a spacing of 0.1 inches. They are white, black, and red electric wires. 

Purchase it from an electric part store or from an online portal. With it, you can perform the procedure efficiently. Gather the required tools before starting the bypass activities.

Find a screwdriver, soldering machine, nuts holder, lighter, scissors, and insulation tape for electric wires. 

Drive the vehicle

Consider the safety features while bypassing the switch of the fuel pump.

For this purpose, drive the Honda Civic for around 7 to 10 minutes in a spacious parking space. Then, engage the gears of parking mode and stabilize the car.

Turn off engine

Switch off the ignition and leave the engine for a few minutes. Allow it to cool down before handling the electric equipment. 

The preventive measure secures the driver from sudden electric shocks. Also, it reduces painful injuries and decreases time consumption. 

Remove the power cables and battery

Access the Honda Civic battery and find the negative terminal. Loosen its connector, rotate it anti-clockwise, and remove it from the power source.

Then, disengage the positive terminal and leave the system for a few seconds. 

Disengage the battery from the integrated power module and keep it aside. It provides enough space to bypass the built-in relay with a 3-end wire. 

The cable removal is a complicated activity due to their factory installation. The integrated power module has a cable that supplies the electric current to the switch cords. 

For their removal, use a nut extractor, adjust it over the bolts and hold them.

Then, turn them in the opposite direction, loosen, and remove them. Then, open the circuit board to access the fuel pump switch.

Access all the holding nuts and remove them with mechanical pulling. Avoid excessive force because it can break the connectors in the circuit board. 

Adjust two screwdrivers around the IPM and pull it. Then, separate it from the system and keep it aside. 

Remove connectors

Access the 40 and 50-pin connectors in the integrated power module circuit board. The 40-pin object lies under the circuit, and the 50-pin is at the top.

Access their sockets, hold the connectors and unplug them manually. The bypass procedure involves the identification of a brown cord on a 40-pin object.

Cut it with the scissors and disengage it from the top surface. Provide heat on the head with a lighter and peel it off. 

Connect the connector with the brown cord of the 3-jumper wire. Solder the connection with a soldering machine and join them firmly. 

Apply electrical tape around the connection and secure the system from short circuits. Next, connect the 50-pin connector to the pink and blue ends of the jumper cord.

Peel the end of the pink cord with a sharp blade and never disengage it from the 50-pin connector. Then, connect the pink part of the 3-jumper cord to the pealed portion. 

Adjust the three-jumper wire

Take a rubber or plastic knot; tie the circuit cords and jumper wire together. Secure the system from disengagement, irregular current flow, and sudden stalling. 

Reinstall removed parts

Readjust the removed battery in the adjustment space, connect the negative and positive terminal, and turn on the car. Check the electric flow and ratio of voltage.

Return the 40 and 50-pin connectors to their built-in sockets. Readjust the IPM and switch cords in their original positions. 

Secure the fuel pump relay

Use a screw, adjust it in the switch and tighten it. Secure its position in the circuit board and avoid flexible movements. 

Why should you not bypass the main relay on a Honda Civic?

Several factors and internal faults of the switch lead to bypass techniques. However, it is dangerous for engine performance and overall vehicle control. 

Insufficient performance of the switch

The alternative ways result in the faulty performance of the relay. It cannot provide enough electric voltage to the computer system and other gadgets.

The electronic features turn on due to electric surges. But, they do not provide enough results due to inappropriate techniques. 

Irregular electric flow

Irregular current flows through the jumper records due to unstable connection. The inappropriate wrapping and insulation lead to leakage of voltage. 

The electronic appliances do not get enough voltages for their standard performance. The fluctuation of current causes short circuits and burns the gadgets.

The low spark for ignition

The switches facilitate a constant spark for ignition and start the vehicles. But, the different techniques cannot provide a similar spark.

Also, the system loses the intensity to turn on the engine in one strike. This is because the protective layer melts, and the electric current loses its effectiveness mid-way. 

Lack of fuel flow

The fuel flow reduces due to alternate switches and market cords. As a result, it does not reach the fuel injectors and affects the combustions in V6 and V8 engines. 

The faulty injectors cause engine misfiring and sudden failures. For example, the Honda Civic idles due to malfunctioning components of the engine.

Clicking sounds of switches

The new connectors, jumper cords, and soldering produce clicking sounds in high-speed conditions. It annoys the driver due to reduced fuel economy, insufficient electric supply, and frequent battery repair.

Reduced engine life

The bypass techniques shorten the lifespan of an engine because they cannot support the standard functions.

Also, the internal damages, constant repairing, and frequent maintenance make the motor vulnerable.

The lubricants do not work with the additional components. As a result, the frictional force increases and causes engine failure.

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