55 400 instrument performance

Posted by happy On 2022/8/26 10:28:18

Instruments not working 55 400
Bought “used tested” voltage reducer. Tested it on a known working 56 system, worked ok. Mounted voltage reducer on 55. Turned power (aux). Temp gauge went to mid-range with the engine stone cold, fuel gauge at E with 15 gallons in the tank. Emptied and dropped tank. Removed sending unit with the feed wire attached, grounded sending unit., and moved the float up and down. Gauge responded correctly. Ensured wire covered with electrical tape, installed tank, Put 10 gallons in tank. Powered up, Gas gauge at E temp at mid-range. Engine cold.
I'm stuck! Any suggestions?
Happy