Any automatic transmission vehicle has a neutral safety switch. It is an electronic component that prevents the starter from working while the car is still in gear. The neutral safety switch is the reason why you can only start your vehicle once you place the gear in ‘Park’. Essentially, it keeps the engine from starting accidentally. It goes without saying that it is essential for you to test the switch and ensure that it is not showing any signs of problems.
When there’s something wrong with your neutral safety switch, you will notice:
- Your car starting in other gears apart from Park or Neutral
- Your backup lights not coming on when you’re in reverse
- The gear selection on the dashboard not corresponding with the shift lever selection
- The vehicle starting in Neutral only
- The vehicle not starting at all
When you see these signs, you must perform a series of tests and perform a neutral safety switch bypass, if necessary. The worst-case scenario is replacing the component. You may have to test your neutral safety switch with a test light, a small jumper wire, or a digital multimeter (DMM). Make sure you follow the steps carefully to ensure that your neutral safety switch remains intact.
First Step: Locate the Neutral Safety Switch
If you do not know where the neutral safety switch is, your best bet is to consult your service manual. It is worth noting that its position varies depending on the vehicle model. It should look like a cigarette lighter, and typically, it is located by the shift mechanism. If you have a column switch car, you should look near the gear shifter. The neutral safety switch should be threaded onto the side of the transmission.
Second Step: Check the Wiring
Now, the next thing you need to do is check the wiring. The neutral safety switch has wires that connect it to the starter solenoid. When your transmission is in gear, the switch will remain ‘open’. Once you move the ignition switch to the Start position, the current will flow to the starter. Just make sure that the transmission is still in Park or Neutral. Also, remember to consult your service manual to get information about the wiring layout of your vehicle. After that, disconnect the switch from the wiring connector.
Third Step: Test the Neutral Safety Switch for Power
Place the gear in Reverse position, then put the key in the ignition switch. Do not turn the engine on yet. You need to check whether the wiring harness has any power. To do this, you must use a 12-volt test light. You will know that there is power when the test light shows an illuminated bulb. This will also tell you that the circuit is functioning properly. Now, you need to attach the wiring connector back to the neutral switch. If you do not see the test light illuminating, you must test all the wires to see if there are damaged or loose connections. If you still do not get any power, then it is time to replace your neutral safety switch.
Another way of checking if you need to adjust the switch is by turning the shift levers to different positions while you’re starting the engine. Essentially, you are performing a neutral safety switch bypass with this procedure. Now, you may wonder if this is safe to do. If you follow the steps below to a tee, you won’t do any harm to your vehicle:
- Put the gear to Park, then try to start.
- If you notice the engine not cranking, step on the brake, then try starting in Neutral.
- If the engine starts, then the neutral safety switch has gone bad.
We hope you learned something useful from this post. If you want to get more tips for preventing car troubles, please do not hesitate to browse through our blog articles!
Didn’t realize how important this switch is or dangerous when bad. My back- up lights wouldn’t come on in reverse. Fuse was okay, light bulbs were okay, I found out problem had to be in the neutral satety switch !! Part was only 65$ my mechanic installed in 1/2 hr , labor 66$. All is okay again.