KEY1 and KEY2 wires are often found on an Android Headunit loom with little or no explanation of where to connect them or what they are for.
We have the answers to the following:
- Do you need to connect KEY1&KEY2?
- Will the Android headunit work if you don’t connect KEY1 or KEY2 wires?
- What are the KEY wires for?
- What is the KYE wire marked on the wiring loom for?
- Where do you connect KEY1 on the Android headunit?
KEY1, KEY2, and GND are the old style Steering Wheel Controls (SWC) control lines. The old-style SWCs are analog and appear in very old cars, and cars are no longer made with that system fitted. But, the KEY1 KEY2 analog has become a standard for manufacturers to use when connecting to an Android Headunit. The KEY1 KEY2 is universal and not tied to a particular vehicle manufacturer.
If you have a modern vehicle with factory-fitted SWC, a ‘Connects2’ style adaptor is required to convert the digital system to the universal ‘KEY1, KEY2, GND’ system. Instructions are supplied with the Connects2 showing which way to connect the KEY1 KEY2 wires.
Not using an SWC (no KEY1, KEY2 connection)
If you don’t want to use any SWC, Insulate each of the 3 wires (KEY1, KEY2, and KEY-GND) and tuck them out of the way behind the Android headunit. Please don’t cut them off! You may add SWC later; having the wires intact will make a future connection much easier to complete.
Aftermarket SWC install
The connection is very simple if you have purchased an aftermarket SWC with your Android headunit.
This is our step-by-step KEY1 KEY2 guide for you.
Time needed: 10 minutes
If your SWC has TWO wires (e.g., Red and Black)
- Identify the KEY 1 wire on the Android headunit
It is usually marked KEY1, DVD, KYE1
- Join using a crimp or solder
Join KEY1 of the Android Headunit to the RED of the SWC
check and insulate the joint
- Identify the SWC KEY-GND wire on the Android Headunit
Join KEY-GND of the Android Headunit to the BLACK of the SWC
check and insulate the joint
- Identify the KEY 2 wire on the Android Headunit
Do not join this wire.
If your SWC has 3 wires (KEY1 and GND), the third wire is KEY2
- Your connections are complete
- It doesn’t work?
Go through the steps again, but use the KEY2 connection on the Android headunit instead of KEY1. Some need KEY1 connections, and others require KEY2 connections.
Android Headunit Tip
Typos are common with Chinese instructions, and you can see KYE1 instead of KEY1 or KYE2 for KEY2 for an Android headunit wire. They mean the same KYE=KEY. You may also see DVD1, DVD2 or just DVD wire, these are also names for KEY1 and KEY2
Success with KEY1
Hopefully, you have correctly connected KEY1 and sometimes KEY2 to your Android headunit. This can be tested with the steering wheel, remote control, SWC app, or settings menu. Your next step is to see if it is necessary to configure each remote control button to a setting on your Android headunit. Common features are volume up and down on the Android headunit mapped to two prominent buttons on the stalk. Often, the chosen controls for volume are marked VOL+ and VOL-, but they could just be + and -. The great thing about the SWC pairing with KEY1 is that you can map whichever button on the SWC to whichever option you want on the Android headunit, giving you a high level of flexibility to control your sounds.
A long press
A long press is often all that is needed to initiate the KEY1/KEY2 pairing in the App. If the configuration is not obvious and you don’t know how to map the buttons, try a long press on the icon for the feature you want to map in the App and follow the prompts.
If you don’t have an SWC app, your KEY1/KEY2 work will be wasted. Help is at hand for owners of later processor Android headunits, which comes as an aftermarket SWC app.
You can find the SWC app on the Play Store here. If you find the App helpful for your SWC/KEY1 setup, please leave rabbity417 a review on the Play Store for their hard work. Not all Android head units will be compatible, so please don’t complain about that on the SWC review, as it is not the APP’s fault.
Joying KEY Connector
If you have a Joying Android headunit with the KEY connector, there are some very Joying-specific instructions on connecting these cables. Joying KEY connection also depends on the vehicle into which the Joying is being installed. If you need Joying KEY information, check our JOYING KEY article for information on how those small black connectors work.