Water Temperature Gauge Does Not Operate. - Mazda MX-5 1990 Workshop Manual

T
INSTRUMENT CLUSTER
Symptom: Water temperature gauge does not operate.
Preparation
SST
05UOTX·466
49 0839 285
For inspection of
gauges
Checker, fuel and
thermometer
~ \
/ >---
~
WATER
~
\ THERMOSENSOR /
~ (/~
~
\ , . t - :.i:::===~
~ ~.
~~-.
T-30
(1B30)
1930
(1830)
183fl
(1BO)
200
) ... CANADA MODEL
(180)
20fl
) ... CANADA MODEL
05UOTX·456
05UOTX·457
05UOTX·281
05UOTX·282
05UOTX·052
Step 1
1. Disconnect the connector from the water thermosensor.
2. Connect the red lead of the SST to the connector, and the
black lead to a body ground.
3. Set the SST to the resistance values shown in the figure.
4. Turn the ignition switch ON, and check that the needle in-
dicates the correct values.
Gauge displays correct Action
Yes
Replace water thermosensor
No
Go to Step 2
Caution
• Continue the above checks for at the least two
minutes each to correctly judge the condition.
• The allowable indication error is twice the width of
the needle.
Step 2
1. Remove the instrument cluster. (Refer to page T -33.)
2. Apply 12V to terminal 2k and ground terminal 2j.
3. Connect the red lead of the SST to terminal 21 and the black
lead to a ground.
4. Set the SST to the resistance values shown in the figure.
5. Verify that the needle indicates the correct values.
Indicates correct Action
Yes
Repair wiring harness
(Instrument cluster - Water thermosensor)
No Replace water temperature gauge
Caution
• Continue the above checks for at least two minutes
each to correctly judge the condition.
• The allowable indication error is twice the width of
the needle.