How to Jump a Fan Relay

To jump a fan relay, remove the relay from its socket and use a wire to connect terminals 30 and 87. If the fan does not start, try reversing the connection.

  • Start by testing the relay to see if it is getting power
  • If not, then you will need to find the fuse box and check the fuse for the relay
  • Once you have confirmed that the relay has power, you can test it by jumping it
  • To do this, you will need to remove the relay from its socket and connect one end of a jumper wire to the terminal marked “86
  • ” Then connect the other end of the jumper wire to a good ground
  • If the relay is good, then when you jump it, you should hear a click
  • This means that the contacts inside the relay are closing and allowing power to flow through

How to Bypass Cooling Fan Relay

When your car’s cooling fan relay is not working, there are a few ways you can bypass it. One way is to use a test light. Another way is to use a multimeter.

If you’re using a test light, simply attach the alligator clip to one of the wires going to the cooling fan. Then touch the other end of the test light to ground. If the test light illuminates, then you know that power is getting to the cooling fan.

If you’re using a multimeter, set it to ” Ohms” and touch one of the leads to each of the wires going into the cooling fan connector. If there is continuity, then power is getting to the cooling fan.

How to Jump a Fan Relay



How Do You Jump a Cooling Fan?

Assuming you would like tips on how to jump a cooling fan: If your car’s cooling fan isn’t coming on, the first step is to check the fan relay. The relay is what actually turns the fan on.

If the relay has failed, it will need to be replaced. If the relay is getting power but not sending it to the fan, then it may just need to be cleaned or replaced. If you have checked the relay and it is working properly, then the next step would be to check for a blown fuse.

The fuse protects the circuit from too much current and if it is blown, then it will need to be replaced before proceeding. Once you have checked and replaced both the fuse and relay, if necessary, the next step would be to test for power at the fan connector. If there is no power at the connector, then tracing back through the wiring harness will be necessary to find where the break in continuity is occurring.

Once you have found where there is no power, repair or replace that section of wire and retest for power at the connector. If there IS power at the connector, then disconnect it and test for continuity between each of the wires going TO THE FAN MOTOR itself. One of these wires should have continuity with ground (usually black), one should go hot with ignition ON (usually red), and one should go hot ONLY when engine temperature demands cooling (this could be a green wire OR a yellow wire depending on application).

IF all three of these things test good AT THE FAN MOTOR CONNECTOR…then suspect an INOPERATIVE COOLING FAN MOTOR itself!

How Do You Test a Fan Relay Switch?

A fan relay switch is a device that controls the flow of electricity to a fan. There are two main types of fan relay switches: those that control the speed of the fan, and those that turn the fan on and off. The most common type of switch is the latter, which is what we will focus on in this article.

The first step in testing a fan relay switch is to check the power supply. Make sure that the power to the switch is turned off before you begin testing. Next, use a multimeter to test for continuity between the two terminals on the switch.

If there is continuity, then the switch is working properly. If there is no continuity, then you will need to replace the switch. To do this, simply remove the old switch and install a new one in its place.

Be sure to follow all safety precautions when working with electricity.

How Do I Know If My Fan Relay is Blown?

If your car’s fan relay is blown, there are a few ways to tell. One way is to check the fuse box for a blown fuse. Another way is to listen for a clicking noise when the ignition is turned on; this indicates that the relay is not working properly.

Finally, if the fan does not come on when the engine is hot, this also indicates that the relay may be blown.


How Do I Run a Radiator Fan Directly to the Battery?

If you want to run a radiator fan directly to the battery, you’ll need to connect the positive terminal of the battery to the positive lead on the fan, and connect the negative terminal of the battery to the negative lead on the fan. Make sure that all connections are tight and secure before turning on the power.

How To Bypass Fan Relay in 1 Minute !!


If your car has an electric cooling fan, it probably has a fan relay. Fan relays are used to protect the fan motor from damage by controlling the amount of current that flows through it. If the fan is running all the time, or if it’s not coming on at all, the problem is likely with the fan relay.

Here’s how to jump a fan relay: First, locate the relay. It should be near the battery or fuse box.

Once you’ve found it, remove the cover and identify which terminals are which. The terminals will be labeled “30,” “87,” and “85.” Next, take a jumper wire and connect terminal 30 to terminal 87.

This will bypass the relay and send power directly to the fan motor. If the engine is running, you should hear the fan come on immediately. If not, turn on the ignition and try again.

Once you’ve confirmed that thefan is working, turn offthe engine and disconnectthe jumper wire. Replacethe cover onthe relay boxand you’re done!