23
May
Once more get out your test light and ground it as you did when you checked the fuses. Multimeter test of brake light switch The loose connection warning message and multiple warning lights can appear if the battery is faulty or not fully charged.
Attach the test lamp to a suitable earth and again hold the brake pedal down with the ignition on.
How to test brake light switch with multimeter. This is how you test your brake light switch with a digital multimeter. All you have to do is to set your multimeter to Ohm meter Ω connect each of the two probes to the terminals of the brake light switch and check if the readings change when the plunger is ON or OFF. You can use the ohm meter set on its lowest scale or the continuitydiode test setting.
Connect the leads to the two terminals and then apply pressure to the brake light switch. On the ohm scale it will go from open to an ohm maybe half an ohm depending upon the connection and internal resistance. A multimeter can be used to test a brake switch.
With the brake pedal released there should be voltage entering the switch and no voltage out. After pressing the pedal in and completing the circuit voltage should be present at both ends of the brake light switch. Some switches have multiple wires for accessories like cruise control.
The manufacturers manual will provide a diagram to identify these pins. Always confirm where a wire leads before testing it. Multimeter test of brake light switch The loose connection warning message and multiple warning lights can appear if the battery is faulty or not fully charged.
Stilo Parts For Sale. Connect Nav Map Discs - Wiper Motor NEW - JTDJTDM Front Brake Discs NEW - 5 of 21545-17 Alloy Wheels. Digital multimeters are cheap and reliable and small also multi ranging which helps to avoid reading mistakes.
When testing your brake light circuit probing the terminals at the switch with the ignition on you should read approximately 12 volts press the pedal and the volts should fall to 0 volts. The brake light switch can be tested with a multimeter without removing it from the vehicle. In some cars the testing procedure involves testing the voltage at the brake light switch connector when the brake pedal is depressed and released.
Move the positive lead to the other wire on the switch. The test light should not come on or volt meter show no voltage. With the leads in place depress the brake pedal.
The test light should illuminate or volt meter read 12 volts if the brake switch is operating properly. Otherwise the switch is defective and should be replaced. The Brake Light Switch.
The picture below shows the brake light switch as used in the fortwo. The Roadster version is the same but without the black rubber bellows over the switch slider. You will need a multimeter to test the switch.
There is no excuse not having a multimeter these days as you can buy them for as cheap as 5. Once more get out your test light and ground it as you did when you checked the fuses. Place the sensor on just one of the two wires and hold the brake pedal down as you do so.
Then test the other wire. If power is connected and the switch is working properly the test bulbs will illuminate. If it doesnt light up the brake light switch is.
Using a meter to test your brake lights and brake light switch. Set your multimeter to DC volts. The brake light system is hot at all times meaning you dont have to have the key turned to the RUN position.
Connect the black lead of the meter to a good ground. Using the red lead touch each terminal on the brake light fuse. If current is reaching the output side of the fuse suspect a fault with the wiring to the brake switch or switch itself.
Attach the test lamp to a suitable earth and again hold the brake pedal down with the ignition on. Touch the probe of the test light to each of the switch terminals in turn. If the light only illuminates on one terminal the switch is faulty and should be adjusted or replaced.
To check this disconnect the wires to the switch. Suppose the brake lights work properly. Test for brake light switch power.
Locate the wire connector that plugs on the brake light switch. Use a voltmeter and probe the power source area. To test a single pole light switch touch one multimeter lead to each of the side terminals.
When you flip the switch on the multimeter should show a reading of 1. To test a three-way switch hold one multimeter lead to the common screw and touch the other lead to one of the travelers. Put the switch into the OFF position.
The meter should display OL or a very high resistance meaning the switch is OFF. Operate the switch on and off for a few more times. If the meter display changes from ON condition to OFF condition the switch operates normally.
If the display does not change from ON to OFF condition. The larger set of pins have more current passing through them than the other two so to carry out the test on the brake light switch get your multimeter connect the red probe to one of the larger pins and the black probe to the other larger pin. Do the same to the other set of pins and then press the switch.
Test for power at the socket. Turn on the light switch then ground the tester to a clean screw on the body of the car. Probe the contacts to see if the tester lights.
If the contacts look corroded scratch the surface but be careful not to bend or distort them. Using a paper clip or similar object jump the connections in the brake light switch plug. Do the brake lights come on.
Yes - replace the brake light switch. No - leave the jumper in place and trace the GREENRED usually wire from the brake light switch plug to the steering column connector. Did you find a break or bad connection.