How to Troubleshoot the dashboard gauges on an LLV postal truck

The United States Postal Service (USPS) use what's called a Grumman Long Life Vehicle, or LLV, for their postal trucks. This video will show you how to troubleshoot the dash gauges in an LLV that are acting crazy. If you;re a mechanic and you have the same sort of electrical problem with the gauges when using turn signals or hazards, this video will help you find the solution, which could involve the parking brake.