Download TSP Coil Driver Output OORH

TSP Coil Driver Output OORH
High Source Driver Is Off, Low Source Driver Is On, And Feedback Current Is Greater Than
Threshold.
POSSIBLE CAUSE
A. COIL DRIVER OUTPUT/DRIVER RETURN SHORTED TO BATTERY
B. COIL DRIVER OUTPUT/DRIVER RETURN OPEN CIRCUIT
C. VALVE COIL OPEN CIRCUIT
D. FUNCTIONAL VALVE FAILURE
E. FUNCTIONAL FAILURE IN CONTROLLER
NOTE
COMPONENT OPERATIONAL CHECK
PROCEDURE OR ACTION:
1. Turn power to OFF for no less than 30 seconds, and then to ON to clear displayed DTC.
Does reported DTC reoccur?
YES: Go to Step 2.
NO: Problem not verified. Resume operation.
2. Conduct a quick visual inspection of all connectors/wiring associated with the displayed fault code.
Are any faults detected/observed?
YES: Repair/replace connector or wiring associated with faults found. ……
NO: Go to Cause A.
CAUSE A - COIL DRIVER OUTPUT/DRIVER RETURN SHORTED TO BATTERY
PROCEDURE OR ACTION:
NOTE: The coil drive control signals, where two valves are shown in schematic, share a common
return.
1. Ensure truck power is OFF.
2. Disconnect connectors from indicated control valve(s).
3. Disconnect indicated VSM connector.
4. Set DMM to volts scale.
5. At the valve harness connector, measure voltage across each coil driver/return output pin (+) and
negative terminal
of battery (-).
Is the voltage on either coil driver/return pin equal to battery voltage?
YES: The pin indicating battery voltage has short circuit to an unswitched battery source. Refer to
electrical
schematics in Diagrams and Schematics for possible source of voltage. Locate and repair/
replace shorted wire/connection…..
NO: Go to Step 6.
6. Turn truck power ON.
7. Repeat measurements from Step 5.
Is the voltage on either coil driver/return pin equal to battery voltage?
YES: The pin indicating battery voltage has short circuit to a switched battery source. Refer to
electrical schematics
in Diagrams and Schematics for possible source of voltage. Locate and repair/replace
shorted wire/connection.
NO: Go to Cause B.
CAUSE B - COIL DRIVER OUTPUT/DRIVER RETURN OPEN CIRCUIT
PROCEDURE OR ACTION:
1. Ensure truck power is OFF.
2. Disconnect indicated connector at VSM.
3. Change DMM to ohms scale. Verify DMM zero reading.
4. Measure the resistance between the valve connector and the VSM connector on the each coil
driver/return pin.
Is the resistance less than 0.5 ohms?
YES: Go to Cause C.
NO: The coil driver/return circuit is open. Locate and repair/replace the open wire/connection.
.
CAUSE C - VALVE COIL OPEN CIRCUIT
PROCEDURE OR ACTION:
1. Ensure the truck power is OFF.
NOTE: The base coil controls flow into the bottom of the cylinder and the rod coil controls flow into the
top /rod end
of the cylinder.
2. Disconnect connector on base control valve coil.
3. On (base) control valve coil connector, measure the resistance between the pins.
Is the resistance greater than 10 ohms?
YES: The coil in the (base) control valve is open. Replace valve coil.
NO: Go to Step 4.
NOTE: Perform Step 4 and Step 5 only if a second valve is indicated on schematic. Otherwise,
proceed to Step 6.
4. Disconnect connector on (rod) control valve coil.
5. On (rod) control valve coil connector, measure the resistance between the pins.
Is the resistance greater than 10 ohms?
YES: The coil in the (rod) control valve is open. Replace valve coil.
NO: Go to Step 6.
6. Verify all procedures in Cause A through Cause C have been completed.
7. Repeat Component Operational Check.
Does DTC reoccur?
YES: Go to Cause D.
NO: Problem not verified. Resume operation.
CAUSE D - FUNCTIONAL VALVE FAILURE
PROCEDURE OR ACTION:
1. Ensure the truck power is OFF.
2. Replace control valve.
3. Repeat Component Operational Check.
Does DTC reoccur?
YES: Go to Cause E
NO: Problem has been corrected. Resume operation.