How do I Find a Bluetooth Phone that is Compatible with ECO?
Although there are many phones to choose from these days, you will need to decide what you would like to be able to do with the phone. If you just want to use your phone for placing and receiving phone calls, we recommend you take your device to your local cell phone provider and try some phones out with your device in hand. You will need to look for a phone that is bluetooth compatible.
If you are wanting to place calls AND text message, we have found that your options will be very limited since most cells phones are not capable of sending and receiving text messages using a Bluetooth signal. Compatible phones available by Sony Ericsson: W580, W350, W760a, W518a and Equinox TM717. These phones were tested using A T & T and/or T-Mobile wireless support.
Due to constant change with technology, the phones listed may have been discontinued since this article was posted. Please check with your service provider for a list of available phones.
When pairing with a new phone, you will use the Phone Configuration screen.
1. From the PHONE Activity Row, select the PHONE DIAL PAD key .
2. Select the Phone Configuration key. 
3. On your phone, go to the "Bluetooth Menu". To find this menu you may have to read the manual that came with your phone.
4. Put your phone in "discoverable" mode.
Note: "Discoverable mode" on your phone may be labeled "discoverable" or "paired" or "find me" or something else entirely. Different Bluetooth cell phones call the pair button different things. If you are unsure which option to select, look at the instructions that came with your cell phone.
5. On your ECO select the Pair to Phone key . 
TIP: If you are having trouble with the phone pairing to the device, try pulling the battery pack on the phone and re-installing it to see if the phone and device will pair now.
6. Your phone will display a message asking you to enter a passcode.
On your phone, enter four zeros: 0000. You must use this passcode. Then select OK or
the button on your phone that accepts your selections and exits.
7. When your cell phone is paired with the device you will see "Paired" or "Connected" in the Bluetooth Status box in the Phone Configuration Menu. If the phone has Bluetooth Texting as an option, you will see TEXT MESSAGING SUPPORTED under the phone name. You will also see Bluetooth cell phone icons in the Status Display Area of the device.
Bluetooth Icons Visible in Status Display Area
The green figure to the left of the cell phone indicates the battery charge. A blue phone indicates you are not using the phone.
The green phone indicates that you are talking on the phone.
This icon indicates that you are making or receiving a call.
The Paired Devices key allows you to view all the Bluetooth cell phones you have been paired with.
The Disconnect key allows you to disconnect (or "un-pair") from the phone you are currently using.