coolant temp gauge inop- does it matter?

[jeronlines]

So, just bought my "new" used 2000 limited with 160k miles. about 200 into the trip home, the coolant temp gauge died.

The Oasis report showed some early issues that I knew about, but the current (third) owner assured me he had no problems. Two questions-
1) what could be wrong
2) worth fixing? the oil press sensor works, but no temp so...it is a problem, right?

Yeah, I'm not a diesel mechanic.

3k miles
Cust Comments: CUST STATES TEMP GAUGE INOP
lTech Comments: SENDING UNIT DIAG REPLACE INSTR. CLUSTER. PER HOT LINE, REPLACED TEMP SENDING U

10884 miles
Cust Comments: CUST STATES TEMP GAUGE FLUCUATES AND IS INOP INT.. Tech Comments: SENSOR DIAG REPLACE COOLANT TEMP SENSOR AND CONNECTOR

14401 miles
Cust Comments: CUST STATES TEMP GAUGE INOP
Tech Comments: CONNECTION DIAG TRACE WIRING FOUND TERMINAL AT TEMP SENDING UNIT

2nd Owner- 66060 miles
Comments: VEH NOT WARMING AFTER 20 MILES OF
Tech Comments: DRIVING PER CUSTOMER REPLACED THERMASTAT ENGINE WARMS UP TOO