Voltmeter going dead during driving

[Harleystreetglide]

2001 Dodge 2500 Slt 5.9 diesel

This morning a dash signal indicated to check gauges. My volmeter had gone dead. Restart and it comes back on then dies. Any ideas ?
Thanks in advance.

 

[brad325is]

Alternator
my guess

 

[Harleystreetglide]

You were right Brad. Replaced alternator and battery cable lugs with larger new ones. Thanks