I've had this issue for a while. Just installed MAD Electric headlight relays and terminal blocks and everything came out great. When the car is running I'm getting 14+ volts at the battery, alternator, terminal blocks, and horn relay buss bar. BUT .... gage in the dash never reads more than 13 volts tops while idling. Just went for a cruise down the freeway and when the car is at more than an idle the gage goes to around 11. Sometimes even dipping to 10 volts. This is cruising down the freeway doing about 70 too? Is this just a problem because the gage is getting it's reading coming through the dash harness? If that's the case, should I route the gage to the terminal block?