Welcome Visitor! Please take a few seconds and BobH
New Member
- Joined
- Dec 26, 2018
- Messages
- 7
- Reaction score
- 4
- Points
- 3
- Location
- Cedar Park, TX
- Vehicle Year
- 1997
- Make / Model
- Ford
- Engine Type
- 2.3 (4 Cylinder)
- Engine Size
- 2.3L
- Transmission
- Manual
- 2WD / 4WD
- 2WD
I have an '89 Ranger with a 2.3-liter 4-cylinder engine. I am trying to fix some dashboard gauges that don't work.
I tested the temperature gauge itself with several resistors and determined that it is operable. A manual and other sources I found say the temperature sending unit is supposed to provide 73 ohms resistance when the engine is cold and 9.7 ohms when hot. My tests indicate that, if the sending unit did that, the gauge would work correctly.
I bought a new sender, but that didn't help. It started at 167 ohms with the engine cold, and the resistance dropped only to 56 ohms with the engine warmed up. That's only enough to move the needle from below the C to just above it -- definitely not into the middle of the normal range.
All the parts suppliers have web pages that say their senders "fit your vehicle," but they don't list the resistance specs for those parts. It appears that all the parts that "fit" may work in some other vehicles but are not intended for the dashboard gauge in the '89 Ranger.
Do you have any suggestions for getting a compatible sending unit?
A bonus question: I have not looked into this fully, but a separate problem is that the power being supplied to the temperature sender, the oil-pressure sender (which is really a switch and not a sensor) and probably the fuel gauge is only about 6 volts, not 12. What would cause that?
I tested the temperature gauge itself with several resistors and determined that it is operable. A manual and other sources I found say the temperature sending unit is supposed to provide 73 ohms resistance when the engine is cold and 9.7 ohms when hot. My tests indicate that, if the sending unit did that, the gauge would work correctly.
I bought a new sender, but that didn't help. It started at 167 ohms with the engine cold, and the resistance dropped only to 56 ohms with the engine warmed up. That's only enough to move the needle from below the C to just above it -- definitely not into the middle of the normal range.
All the parts suppliers have web pages that say their senders "fit your vehicle," but they don't list the resistance specs for those parts. It appears that all the parts that "fit" may work in some other vehicles but are not intended for the dashboard gauge in the '89 Ranger.
Do you have any suggestions for getting a compatible sending unit?
A bonus question: I have not looked into this fully, but a separate problem is that the power being supplied to the temperature sender, the oil-pressure sender (which is really a switch and not a sensor) and probably the fuel gauge is only about 6 volts, not 12. What would cause that?
