Kubota u15-3 Workshop Manual page 162

WSM U15-3
4. Auto glow circuit
1) Water temperature sensor circuit check
When the water temperature sensor and its wiring function, the engine's water temperature is
detected and the glow plug is preheated for a time required to get the engine started.
2) First make sure the water temperature sen-
sor functions. Disconnect the water tempera-
ture sensor coupler and put your fingers in
slight contact with the glow relay. Now turn
the key switch to the ON position and feel the
glow relay clicking.
• When it clicks, check the glow plug coupler
as well as the glow relay.
• If it does not click, measure the voltage,
check for continuity, and check the glow
relay.
3) Voltage check
• Keep the glow relay coupler in position.
• Turn the key switch to the ON position.
1. Measure the voltage between the auto
glow relay coupler terminals [3] and [4] as
well as between [1] and [2] to see if it is
12 V.
• 12 V reading for both: Check the glow
relay.
• Other reading: Measure the voltage in
Step (2) below. Also check for continu-
ity.
2. Measure the voltage between the glow
relay coupler terminal [4] and the body
ground to see if it is 12 V.
Glow relay
Battery
(5A main power)
II-142
17
-115