Modern technology makes life easier, in a sense. We advance as we look at the best of what we have and improve it in all areas we can—cars are no different. When the ZF 8HP transmission debuted in 2009, it became the go-to automatic transmission to use. Automakers from Alfa Romeo to BMW, to Volkswagen, and many in between, use the ZF 8-speed automatic transmission to this day. And while there are plenty of good things to say about it, there were some oversights made.
You may have noticed that your automatic-equipped vehicle can only be started in park or neutral, and that is because of the neutral safety switch. The switch prevents the vehicle from starting in gear. All modern automatic transmissions dating back at least 30 years have a neutral safety switch. If the vehicle were started in gear, the car would lurch forward, potentially damaging the gearbox and causing you to hit whatever is in front of you.
If the shifter ever becomes stuck in gear in an older vehicle, a small plug on the shifter bezel could be removed. Below the plug is a piece that you could press down allow the shifter to move into neutral while the car is off. However, on the vehicles equipped with the ZF 8-speed automatic, there is nothing to help manually move the shifter to neutral when the car is off. That becomes an issue when the battery is dead, and the vehicle needs to roll onto a tow truck or other similar situations. ZF did put a failsafe in place for these situations but didn't make it the easiest to get to.
Where is the ZF 8-Speed Neutral Safety Switch Bypass Located?
The ZF 8HP neutral safety switch bypass can be found on the bottom of the transmission; there's a bolt positioned below a small foot that comes out of the transmission. That little foot is the manual neutral safety switch bypass. Depending on your vehicle, the location of this bolt could be obscured by various belly pans/plastic panels. You will need to remove these to gain access.
As you rotate the bolt to the right, the foot will move upward. As you push the foot up, the transmission will click into neutral, allowing the car to roll freely.
Tools Needed to Put The ZF 8-Speed Transmission in Neutral:
How to Put The ZF 8-Speed in Neutral:
First start by safely lifting the car in the air. We always advise using a quality floor jack and jack stands to support the vehicle. Once it is in the air, you need to gain access to the transmission. Depending on the car in question, this could be behind belly pans or covers.
Once you've gained access to the transmission, locate the hex-head bolt. Use a 5mm hex bit socket on a ratchet to rotate the bolt to the right. Listen for a click as you move the foot up. The click indicates that the transmission is no longer in park, and the car will roll freely.
After the transmission clicks into neutral, loosen the bolt until there is a gap between the bolt and foot. The transmission will stay in neutral and will be able to be shifted into park with a charged battery. Leaving the bolt tightened will prevent the car from being shifted into park once it is charged.
So there you have it. You’ll never be stuck in gear in your ZF 8HP-equipped car again. If you're interested in more Tech Tips for your European or German vehicle, you can visit our blog homepage at blog.fcpeuro.com and subscribe to our YouTube channel.