A neutral safety switch, as the name implies, is a safety purpose switch which is a common component found in vehicles with automatic transmission. These safety switches serve a simple purpose – limiting the vehicle from starting only in ‘Park’ or ‘Neutral’ gear.
What is a Neutral Safety Switch?
Unlike the manual transmission, the automatic transmission has no driver-operated clutch and no stick shift. In a manual transmission, a car can be started in any gear as long as the clutch is fully depressed but in case the clutch is not depressed and the car is in gear, trying to turn over the engine will cause sudden jerks as if the car is trying to go forward.
In either case, the car will start nonetheless but it can be dangerous as drivers can often forget that the transmission is in gear and accidentally turn the engine over, causing a jerk.
This is prevented in an automatic transmission using a neutral safety switch. This safety switch prevents the ignition from switching on at all when the car is in ‘Drive’ gear or ‘reverse’ or any other gear for forwarding. Even if the driver forgets to put the car in neutral or park, and cranks the engine, the engine won’t turn at all, preventing any hazard.
Sometimes this neutral switch can go bad causing starting problems.
Bad Neutral Safety Switch Symptoms
Figuring out whether a neutral safety switch has gone bad is relatively easy for someone with little knowledge about internal systems of a vehicle. Here are the symptoms to look for to diagnose your car’s neutral safety switch:
The ‘check engine light’ lights up
If your engine light is up and you happen to have an OBD scanner, you can check for the code your car has given. If the code P084F comes up, it means your neutral switch is bad which should pretty much make the trouble code clear.
The car tries to startup in any gear
If you find out that your car’s engine is cranking even though it’s in ‘Drive’ or ‘Reverse’ or any other gear, it definitely means your car’s neutral switch is not working as it should since it shouldn’t be allowing the engine to turn over in any gear other than ‘Neutral’ or ‘Park’. That’s as far as your personal diagnostics can go because further inspections can only be made by a proper car mechanic with the right tools and accurate knowledge of automatic transmissions and their operations.
Car starts only in ‘Park’ but not ‘Neutral and vice versa
Although it’s better than the car starts at least in ‘Park’ and no in any other gear, the switch proves to be faulty in such a case and you should not overlook the situation, but get it checked asap by a certified mechanic because there’s no telling how long the neutral switch can go further so it’s better to get it fixed or changed before any major damage occurs.
The car starts sometimes, but sometimes don’t
If you face this problem that you are lucky your car starts sometimes, it is still possible that your neutral switch has either gone completely bad or failure is imminent. But in such a situation, the problem could be lying elsewhere too, like in the ignition itself, the starter, or the wiring. In any case, you’ll need professional help to resolve this issue. If you come to know that you are able to start your car after shifting the gear stick a couple of times before turning over the engine, then your neutral safety switch is the culprit.
The engine doesn’t turn over at all
An engine not turning over at all could mean a lot of different things. From a bad battery to a faulty ignition and starter. You can check this by checking if the dash lights come on after turning the key half way. Unfortunately, for detailed inspection, you’ll need a professional to look into your car to determine the exact cause of the issue.
Testing & Solutions
Although there are a number of ways you can diagnose your car’s condition to a point, unfortunately, you won’t be able to perform any repairs or replacements yourself as accessing the neutral switch or ignition is difficult. You should consult a trusted or well-known mechanic to perform the diagnostics and repairs. A few things you could do to rule out other causes of the engine not starting:
Check Neutral Switch Parameters
You can check the parameters of the neutral switch to the ECM and Transmission control unit with an OBD2 scanner. Make sure the gear lever is correct and getting the right value of the desired gear.
Check your car’s battery
If your car doesn’t start even in ‘park’ or ‘neutral’, you could check if your battery is okay or not. The easiest way to determine is by checking the lights on your dashboard. If the lights come on, your battery should be okay. Always test to charge it first with a car battery charger.
Check your ignition
You should be able to hear a click when your turn key to crank the engine. If the click can be heard, your ignition is operating. If you hear no click and your engine doesn’t turn over, it could be the ignition although it’s better to confirm your doubts by going to a mechanic.
Check the engine’s starter motor
This can be a little difficult to check if you aren’t comfortable or don’t understand even the basic components of a car. But if you know enough, you could check your starter motor by putting your hand on the motor which is situated a bit deep inside the engine bay, beneath the engine block. If you feel any vibration whatsoever, your starter motor is working. You could also check it by using a voltmeter and checking the readings off of the starter’s terminals.
If none of these components are bad, then it’s highly probably your neutral safety switch has somehow gone bad and you’ll need a certified automatic transmission specialist to check the situation for you.
Neutral switch Replacement Cost
Depending on the make and model of a vehicle, an estimated average cost of switch replacement goes range from $50 to $150. The labor cost can range from $50 to $100