Oldsmobile/Buick Repair: 2004 temp sender, coolant temp, coolant level

Question
2004 buick lesabre 3.8 temp guage has pegged all the way past the red mark. I don't have access to a guage tester. Can you tell  me what the ohm reading would be on the sender, so I can eliminate it. When the key is off, the needle is almost in the red. With the key on, it goes all the way over to the hot side past the red zone. Coolant level is good and both fans are working. The engine is not overheating. And the t-stat is good also. The problem is either in the guage or sender. The car was jump started the day before. Owner feels that might have something to do with it, however, no polarity was crossed.

Answer
Hi
I would HIGHLY suspect the IP Cluster over the temp sender.
The temp sender is s thermistor, so the resistance will vary with coolant temp.You COULD also try to unhook BOTH battery terminals.
Then touch them both together for about 1 min.
After that reattach the POSITIVE first, then the negative.
This will SOMETIMES clear up logic lock th ecluster MAY  be in.
I hope this helps
Pawl
PS
Here is a table for your checks

°C
°F
OHMS

Temperature vs Resistance Values (Approximate)

150
302
47

140
284
60

130
266
77

120
248
100

110
230
132

100
212
177

90
194
241

80
176
332

70
158
467

60
140
667

50
122
973

45
113
1188

40
104
1459

35
95
1802

30
86
2238

25
77
2796

20
68
3520

15
59
4450

10
50
5670

5
41
7280

0
32
9420

-5
23
12300

-10
14
16180

-15
5
21450

-20
-4
28680

-30
-22
52700

-40
-40
100700