How To Bypass Asd Relay: A Step-by-Step Explanation

How to bypass Asd relay? The answer is easy; you can wear a jumper on pins #30 and #87, which control the automatic relay. 

Step by Step Explanation To Bypass Asd Relay

However, it might sound like a lot of work at first, but we will break it down into a simple step-by-step guide below for you. We will also tell you how the automatic shutdown relay works, common symptoms when it gets bad, and other essential information you’ll probably love to know. 

How Can You Bypass Asd Relay With Easy Steps?

To bypass the Asd relay, you need to locate the Asd relay and energize the coil to get a flexible terminal to enable the current to flow and prepare the other contact. After this, wear a jumper on pins #30 and #87.

It’s worth mentioning that you should not confuse Asd with the fuel pump relay. These are two distinct components. The Asd relay is in charge of power to the coil and fuel injectors. On the other hand, the fuel relay is designed to control the current flowing to the fuel pump

As we have said, it’s easy to bypass the Asd relay. First, you’ll need the following essential tools:

  • Wire cutters or strippers
  • Screwdriver
  • Jumper cables

1. Locate the Asd 

Open the power module holding the Asd relay. Examine the spring at the motor’s contact. If the coil doesn’t receive power for a while, you’ll have to spring close the terminals. 

2. Energize the Vehicle’s Coil

Energize the coil to get a flexible terminal, which you’ll pull. That will ensure a flow of current and prepare the other contact. At this point, you must master the Asd relay wiring structure diagram. 

3. Wear a Jumper on Pins #30 and #87

Just below the Asd relay, find the path of the current flow. Even when the coil is not energized fully, the current will flow from that position. Replace the fuel pump with an electric fan. 

You’ll find two pins that control the Asd relay; pins #30 and #87. Wear a jumper on these pins to help you bypass the Asd relay. 

How To Test a Faulty Asd Relay

To test a bad Asd relay, you need to locate the relay, remove it from its socket, and test terminals #30 and #87. Finish up by performing a final test, which involves checking for continuity in the above-mentioned terminals.


A bad Asd relay will cause your vehicle to show various failure symptoms, like the ones discussed above. However, the symptoms can as well come from another source. In that case, it’s good to know how to test your automatic shutdown relay for faults. 

First, you’ll need some tools: jumper wires, a multimeter, or a test light. Next, park your car on level ground. Set the parking brake, turn off the engine and open the hood. Now follow these steps:

  1. Locate the Asd

The Asd relay is often mounted on the inner fender close to the battery. The Asd relay has four terminals with labels #30, #8, #87A, and #89. 

2. Remove the relay

Carefully remove the automatic shutdown relay from its socket. Depending on the make and model of your car, the Asd relay may have a locking tab that you must depress before removing it. 

3. Test the terminals

For terminals #30 and #87A: set your multimeter to the continuity mode and check for continuity between terminal #30 and #87A. If there’s no continuity, the Asd is faulty and needs replacement. 

For terminals #85 and #87: Set the multimeter to the OHMs setting X1 and connect it between #85 and #86. The Asd relay performs properly if the multimeter reads anywhere from 70 to 80 ohms. Conversely, you have a faulty Asd relay if the multimeter reads OL or infinity. 

Terminals #30 and #87: One of these terminals is the de-energized terminal, meaning if you connect the two and there’s no continuity, then the Asd relay is faulty. 

4. Perform the final test

This test is the most critical in determining whether or not the Asd relay is working. Connect terminals #85 and $86 to the negative and positive sides of the 12V power supply, respectively, using jumper wires. That should turn on the relay. 

Set the multimeter in the continuity mode and check for continuity between terminals #30 and #87. If there’s no continuity, your relay is faulty and needs replacement.

Note: Your Asd relay ensures power flow to some of the essential components of your vehicle engine during ignition. So, if it’s faulty, your engine won’t crank. You can’t jumpstart it, either. For that, if you experience a no-start condition, the Asd relay could be the cause. Seek professional diagnosis immediately and get an Asd replacement if necessary. 

How to Recognize the Symptoms of a Bad Asd Relay

A bad Asd relay will cause the check engine light to turn on. It can also cause the engine to fail to start or experience stalls. Other signs include acceleration lag and the Asd relay making a clicking noise.

Recognize the Symptoms of a Bad Asd Relay

It’s essential to know to identify the symptoms of a faulty Asd so you can quickly take action and prevent inconveniences. Thus, here’s a deep dive into the above signs:

  1. Check engine light turns ON

One common bad auto shutdown relay symptom is the Check Engine Light on. If the Asd is faulty, it will probably fail to supply power to the engine control module (ECM), which will illuminate the engine light to notify you. 

A malfunctioning Asd relay may intermittently disconnect power to the ignition coil or fuel pump. If that happens, the ECM will also throw a code and turn on the check engine light. 

2. The engine fails to crank

A faulty starter motor will cause the engine not to crank. Many things can cause this, including a loose connection, a dead battery, or an issue with the starter itself. Surprisingly, a bad Asd can also make the engine fail to crank by not providing power to the ignition system, fuel pump, and other essential engine components. 

3. Engine stalls

Many things can cause engine stalls, and a faulty Asd relay is one of them. As mentioned, a bad automatic shutdown will impact the fuel pump’s performance. A poorly performing fuel pump can cause excessive lean air/fuel mixture, making the engine stall a moment after starting. 

A bad Asd will also not allow a sufficient electric current to flow to the ignition coils. That, too, will make the engine start and stall due to incorrectly firing spark plugs.  

4. Acceleration lag

Another common sign of a faulty Asd relay is a vehicle lagging in acceleration. A problematic auto shutdown relay can stall the engine, especially at low speeds or idling. That can ultimately make it hard to accelerate from a stop. 

Moreover, malfunctioning Asd may cause your engine to run rough and reduce acceleration. Ignition delays and fuel delivery issues can cause acceleration lag, possibly due to a bad Asd. 

5. Asd relay makes a clicking noise

If you hear the auto shutdown relay clicking, it’s primarily due to insufficient voltage to engage it. And that potentially causes the engine control unit (ECU) to detect a low battery condition even when it has a good battery. 

Also, the acid from the battery can cause the powertrain control module (PCM) and fuse panel wires to break. That may cause Asd Relay no ground issue between the fuse panel and PMC and probably trigger the Asd clicking noise.  

How Does Asd Relay Work? 

The Asd relay works as a switch to the essential engine components. It supplies 12 volts of power to the ignition coils and the fuel injectors. That enables them to provide fuel and produce the spark needed to start the car.

Here’s a detailed explanation of how the Asd relay work.

The Asd relay terminal #30 is connected to the battery voltage. The Powertrain Control Module (PCM) grounds the auto shutdown relay from the side of the coil via terminal #85. The voltage flows to the Asd relay coil side through terminal #86. 

When the PCM stops the function of the Asd relay and the fuel pump, terminal #30 will be connected to terminal #87 in an OFF position. At this point, the rest of the circuit isn’t receiving power. On the other hand, when the automatic shutdown relay and fuel pump regain power from the PCM, terminal number 30 connects to #87 in an ON position. And at this point, voltage flows to the remaining section of the circuit through terminal #87. 

In other words, the ignition switch turns on the Asd relay. When you switch the key to the ON position, 12 volts flow to the coil and fuel injectors. That creates a magnetic field that closes the contacts, completes the circuit, and enables current to flow. The Asd remains active as long as the ignition switch is ON and the power goes to the ignition coil, fuel pump, and the engine’s control module.  

When you switch it to OFF, the current stops flowing through the coil, and the contacts open, shutting off power to the ignition coil, the fuel pump, and the engine’s control module. 

When you turn the car back ON, sufficient current must flow to fire up all circuits and start the vehicle. When that doesn’t happen, the Asd relay is probably faulty. 

– How To Reset Asd Relay

You can easily bypass Asd and start your car, but you can’t reset this device. The best thing to do would be to replace the entire power module. The automatic shutdown relay plays a significant role in ensuring the optimal performance of your car engine. 

– Why Does Your Vehicle Need an Asd Relay?

Previously, vehicles had no Asd relays. Nevertheless, times have changed, and this feature has become a necessity. An Asd relay in a modern car is a switch to critical electrical components. It’s also a safety feature and ensures the engine’s optimal performance to give you the best driving experience.

First, modern cars have a more complex electrical system than older models. That means they have numerous components that must be turned off with the engine. If one is left on when the engine shuts off or there’s a short circuit, problems such as a drained battery can arise. The automatic shutdown relay ensures that everything shuts down properly and the engine will start up again when needed. 

Second, the Asd relay is a safety feature protecting your car’s engine electronic management system. This system is composed of many components, including the ECM, throttle position sensor (TPS), knock sensor (KS), oxygen sensor (02), and Mass Airflow Sensor (MAF). 

Additionally, the system continuously monitors the engine’s performance and works to ensure optimum performance and overall fuel efficiency. It also plays a part in reducing emissions by controlling the amount of fuel injected into the engine. 

How to Detect Causes Behind Asd Relay Malfunction

To detect the causes behind Asd relay malfunction, you will need to check some components of your car and engine, such as high temperatures, a damaged motor, and a dirty connection on the Asd relay board are some of the things that cause the Asd to malfunction.

Other causes include:

  1. Insufficient control of the car’s fuel system.
  2. Too high electrical currents flow through the relay.
  3. Chemicals, salt water, and other liquids may have entered into essential components, such as the transistor, connector, and circuit board.

How Much Does an Asd Relay Replacement Cost?

Automatic shutdown relay replacement costs vary depending on the model of your vehicle and location. For most cars, you can expect to pay $80 to $110 for a new Asd relay. However, you will need to dig your pocket deeper for some cars, especially luxury vehicles. 

For example, an Asd relay Jeep replacement can cost you between $120 to $200 or more. For a BMW, the automatic shutdown relay can cost up to $300! A dodge ram 1500 auto shutdown relay costs between $105 to $115. This price is inclusive of parts and labor. The cost of replacing the dodge auto shutdown relay may also vary, depending on the model year. 

How to Know When You Need To Bypass Asd Relay?

To know when to bypass Asd relay is if your car doesn’t start. Another reason is when you’re pressed with time and need a quick jump start. You might also need to bypass the relay when using jumper start cables on another car. 

Bypass Asd Relay when Car Doesnt Start

  1. The car won’t start

The automatic shutdown relay can prevent your car from starting for several reasons. Some of them include a dead battery or a problematic starter motor. If your car can’t start using the usual way, bypassing the Asd relay could be the only option. 

  1. To save time

You may also bypass the Asd relay if you want to save time. For instance, your battery could be dead, but you still want a quick jump start without waiting for the Asd to activate. Besides, Asd sometimes requires time before reopening its contacts after being turned off. That means there may be enough power flowing through the relay, but it will activate slower than you want.  

  1. When using jumper cables on another car

If you want to jumpstart another vehicle whose ignition switch is turned on (or doesn’t have one), you must bypass the Asd relay. That’s the only way you’ll get the car to start. 

Frequently Asked Questions

1. Can a Fuel Pump Run Without a Relay?

A fuel pump relies on the fuel pump relay to get power to perform its function. Therefore, if there’s no relay, there will be no power, and the fuel pump won’t run. 

2. Can I Jumpstart a Car Without Access to the Negative Terminal? 

You don’t need access to the battery’s negative terminal to jumpstart a car. Just connect the negative clamp to a metal ground instead. However, ensure you use an unpainted metal part of your engine block. 

3. What Can Be the Consequences of not Using a Relay? 

Using a relay prevents premature failure of electronic components, notably the switch. For example, when installing an electric cooling fan, connecting it without a relay will damage the switch prematurely. 

4. Can an Asd Relay Drain My Mattery? 

The work of an Asd relay is to ensure the smooth flow of electricity from the battery to the various components of the engine. It serves as a switch for the power to the ignition system. A bad Asd relay can drain the battery and cause ignition failure. 

5. Can I Remove the Jumper Cables While My Car Is Running? 

Yes. However, you must remove the cables in the opposite order you installed them. Start by disconnecting the black clamp from the grounded metal part of the car with the dead battery. Next, disconnect the black clamp from the functioning battery and disconnect the red clamp from the same. 

Working Process of Asd Relay

Can Bypassing the ASD Relay Help Reset the Chevy Transmission Control Module?

Can bypassing the ASD relay serve as a reliable reset method for Chevy transmission control module?


Now you know how to bypass Asd relay, thanks to this article. So, go ahead and do it like a pro! But before that, let’s have a quick summary of what we have learned:

  • You can bypass the Asd relay in three simple steps: locate the Asd, energize the coil to get a flexible terminal, and wear a jumper wire on terminals #30 and #87.  
  • The Asd relay controls the power supply of essential engine components, such as the fuel injectors and ignition. 
  • A bad Asd relay can cause mechanical problems, including engine stalls and crank failure.
  • You can’t reset the Asd relay. The solution is to replace the entire power module.
  • Asd relay replacement costs between $80 and $110 for most cars, depending on model and location.

We are confident you have all the information you need. Grab your tools and bypass that Asd relay. Better yet, have it replaced if it has malfunctioned. 

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