Error 1687, now what?

Error 1687.

If you've ever read a MOTOTRBO radio, you might have come across this error message. It basically means that the radio did not respond.  There are a number of causes for this and many of them can be solved with a few simple checks.

Check the connections. Is the programming cable really plugged into the PC and connected to the radio. Sometimes dirt and other interesting things can get onto the accessory connector terminals - especially portables. An old toothbrush with a little contact cleaner or methanol will make sure those contact are clean.

The portable accessory connector.

Is the cable okay. There is no intelligence in the programming cable. The thick round thing on the cable is just a RF choke. So if you plug in the cable, Windows will not see it as a device.
On that point, if you have a PMKN4012A and a DP4000 series radio, this combination wont work. You will either need to get a PMKN4012B or modify (caveat emptor) your cable to support this (details can be found on the internet).

Is the radio turned on. Even I get caught out by this more often than I care to admit.

Does Windows "see" the radio. Windows will notify you when the radio is connected and disconnected. When the radio is plugged in to the PC, a USB RNDIS driver gets loaded. Here is a video showing the sounds that Windows 7 will produce.

Patience. The RNDIS driver takes a few seconds to load depending on how fast/cluttered your PC is. Wait a few seconds before pressing the read button.

Can you see the radio in Windows. Once the RNDIS driver is loaded, have a look in your Network Connections and in Windows Device Manager. In Network Connections the radio will show up as a network connection with an IP address. In Windows Device Manager the radio will show up as a network adapter.

Did the driver load. If the radio appears in the Unknown Devices tree in Windows Device Manager, then you need to make sure the CPS is installed on this PC or, at the very least, the driver files.

Are you using a USB 3.0 port. These are known to be quirky so try a USB 2.0 port to eliminate this as a cause. USB 3.0 ports will have blue insulator material - USB 2.0 ports are black.

Can you ping the radio. Since the radio is seen as a network connection by Windows, you can ping it. By default the IP address of the radio is 192.168.10.1.

Is the radio okay. If you've checked the above, you might have a defective radio. Try another radio on the same setup: if that radio works then you've narrowed it down to this radio. Have a look at the radio display and check whether the radio works normally otherwise.
If the radio shows up in Windows Device Manager as a FlashZap device then you've "bricked" your radio and it needs to be returned for repair.

If you've done all of the above and are (now) getting another error message, have a look at a post from a while back, on this topic.

Did I miss anything?