Case IH 9250 - Troubleshooting-Sensors and Harnesses

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Diagnostics
Troubleshooting—Sensors and Harnesses
To properly test the wiring and sensors on the header, follow the steps below in order. Use a Volt Meter
as needed.
The sensor connector pattern is as follows:
• Pin A is Ground (Black or Lt Blue)
• Pin B is Signal (White)
• Pin C is 5V (Green or Pink)
A very common problem during install is to reverse the wires at the connector after removing
the plug to route the cables. Make sure that the wires/voltages are as shown. If A & C are
reversed, the voltages will swing backwards.
The following requirements must be met before testing:
• Key on, combine engine running
• Header connected
Error Code Problem Solution
Bad Harness Wiring
Disconnect Sensor Plug
(Measure voltage on harness
plug at sensor)
Measure C to Frame Ground
Voltage should be 5V
If not, check harness for
continuity or short on 5V wire
Check Combine 5V source
Measure C to A
Voltage should be 5V
If not check harness for
continuity on ground wire
Check combine sensor ground
source
Jump C to B in harness plug
Voltage should be 5V
(For Insight systems, see
“Diagnostics/Display Sensor
Voltages”. For all others, use
Combine Diagnostics*)
If not check signal wire
for broken harness or bad
connection
All of the above are correct Harness & combine connections
pass test.
If you have a Headsight Sensor
tester, use it to test the sensor.
For all other:
Verify sensor is connected to
extension harness
Sensor voltage should be 0.5-
4.5V
(For Insight systems, see
“Diagnostics/Display Sensor
Voltages”. For all others, use
Combine Specic Diagnostics)
If sensor cannot be adjusted
to achieve a voltage within the
range, replace sensor.