Neutral Safety Switch on Jeep Wrangler | How to know if it is faulty on Automatic and Manual Transmission
A neutral safety switch is a safety device that is located in the transmission oil pan, combined as one unit together with the backup light switch in automatic wranglers. For manual transmission wranglers, there is a device similar to the neutral safety switch located on the clutch pedal.
This ensures that you can not start your engine unless the pedal is pressed. That device acts as a conductor between the ignition switch and the engine starter.
The neutral safety switch on jeep wrangler will only allow you to start your engine when the transmission is in the park or neutral mode and does not allow you to start your engine while in other gears. This is an important safety feature that your wrangler cannot lack.
If you start your engine while on other gears except for park or neutral it may lead to an accident as your wrangler with thrust backward if in reverse gear and will thrust forward when in other gears. A faulty neutral safety switch cannot be repaired and should be replaced within the slightest indication that it is faulty
Signs of a safety neutral switch On your vehicle
The engine does not crank at all
In this case, it shows that there is no power flowing through the neutral safety switch to the starter which prevents the starter from cranking the engine. The issue is mostly with the circuit that relays power to the neutral safety switch, either there is a blown fuse or the neutral safety switch itself is damaged.
Electrical wires rarely do get damaged but it’s good to check. whether it is the electrical wires, fuse, or the neutral safety switch, whatever is damaged needs to be replaced.
The engine cranks in any gear
This is not supposed to happen as the function of the neutral safety switch is to prevent this from happening as a safety precaution. When the engine cranks in any gear it can thrust forward or backward if it is in reverse gear leading to an accident. When this happens, it is a sign that the neutral safety switch has an internal short circuit and needs to be replaced.
The engine only cranks in neutral
The neutral safety switch only allows you to start the engine either when in neutral or park. This mostly occurs in automatic transmission. When your wrangler is in park gear it does not start and only starts when in neutral gear.
In manual transmissions, the engine does not start in park gear. The neutral safety switch might be faulty but this is also caused by battery and starter issues and it is recommended for a mechanic to check your wrangler to come to a specific conclusion.
The engine only cranks in park
You can only start the engine when in the park or neutral and if you can’t start the engine when in neutral gear and only starts in park gear then there is a problem with the neutral safety switch.
It might be an electrical failure or the neutral safety switch is loose and needs to be re-adjusted. When you notice this, it is good to check the neutral safety switch earlier as when it gets too late it will get damaged and you’ll incur more costs when buying a new one
Check engine light goes on
The check engine light goes on due to several engine and transmission-related issues and since the neutral safety switch plays a part in turning on your engine the check engine light might come on to indicate that it is faulty.
But you should not assume directly that the neutral safety switch is faulty without inspecting whether other engine-related issues check out. If they do then you can proceed to check the neutral safety switch
How to check if the safety neutral switch is faulty?
If you have doubts that the neutral safety switch is faulty, here is how you can check it
Automatic transmission wranglers
- Park your wrangler in an open parking space that you cannot hit anything from the front or the rear.
- Turn your engine completely off.
- Press hard on your brake pedal and turn your key to the “start” position and hold it there.
- Move the gear lever through different positions while starting your engine and it starts in only neutral or park, it is a sign of a faulty neutral safety switch and if it also starts in other gears except for park and neutral it also shows that the neutral safety switch is faulty.
Manual transmission wranglers
For manual transmission wranglers if the engine starts without you pressing down the clutch pedal while starting the engine then you can come to the conclusion that your neutral safety switch is faulty.
Should you bypass the neutral safety switch?
No. Some wrangler owners might think of removing or bypassing the safety switch which is not a safe option as it is installed on your wrangler as a safety feature that prevents your wrangler from thrusting forward or backward which might lead to an accident.
How to access neutral safety switch in automatic Jeep wrangler?
- Park your wrangler in a flat spot and engage the emergency brake.
- Open the hood and hold it in place with the hood support and then remove the clamp on the negative terminal of the battery. You can keep the hood open or close it after removing the negative terminal clamp.
- Jack your wrangler up to the desired working height and put jack stands under the vehicle fame at four points closest to the wheels.
- Lower your wrangler slowly onto the jack stands and remove the jack.
- Get under your wrangler and place a container under the oil pan to catch the transmission fluid when you open the oil pan.
- Loosen the screws that hold the oil pan in place and let the oil drain into the container.
- Detach the wiring harness from the neutral safety switch which will allow you to remove the safety switch by unscrewing the screws that hold it in place.
- After the neutral safety switch is out you can check it for any dirt that maybe makes it faulty while checking for other damages that might make it faulty.
Disassemble the switch by removing the screws on the plastic cover, check for any electrical damages on it and if there is none, your switch is okay and just needs some cleaning.
Since the safety neutral switch is an electric device, clean it with electric contact and a soft small brush. Using other cleaners will damage the contact points. Apply sealant on the plastic cover and reattach the neutral safety switch to its place.
- If the switch is damaged, it cannot be repaired and you need to replace it with a new safety switch specifically made for your wrangler’s model and year of manufacture.
- Secure the new switch into place by screwing the screws that hold it there and reconnect the electrical harness.
- To test the old or new safety switch functionality reconnect the negative terminal clamp onto the battery and try starting your engine in neutral or park gears, then try starting when in other gears.
- If the engine starts in both neutral and park gears only then the neutral safety switch is good. If the engine starts only in one gear either neutral or park the neutral safety switch is faulty and it is also faulty if it starts in other gears. When either happens, you need to replace the neutral safety switch.
- Once you have confirmed that the neutral safety switch is in good working conditions, disconnect the negative battery clamp and reinstall the oil pan. Make sure everything is in place before lowering your wrangler and reconnecting the negative terminal clamp.
- Close the hood and you can test drive your wrangler while testing the neutral safety switch at intervals.
How to access the neutral safety switch in manual jeep wrangler?
- Park your wrangler and engage the emergency brake.
- Push the driver’s seat as far back as possible to give you room for working.
- There are two screws next to the clutch pedal that holds the neutral safety switch to the floorboard if they are loose tighten them.
- Neutral safety switches in manual wranglers rarely get damaged and if they do you’ll have to seek assistance from an authorized mechanic as the wiring from the ignition to the neutral safety and the wiring from the neutral safety switch to the starter may differ in different wranglers.
Conclusion
A neutral safety switch is installed on all wranglers as a safety feature and you should have it functioning at all times to avoid causing accidents. Some owners might want to bypass the neutral safety switch which is never recommended at all as it might lead to serious accidents.
Replacing or servicing a neutral safety switch by yourself can be tricky and if you have any doubts about it you should have it done by a certified mechanic.