Pinpoint Test A : An Auxiliary Switch Controlled Component Is Inoperative
WARNING: This page is about a different car, the 2019 Ford F-550 Super Duty, 2019 Ford F-450 Super Duty, 2019 Ford F-350 Super Duty, and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
- A1 PERFORM INSPECTION AND VERIFICATION
- Perform Inspection and Verification procedure in this information.
Was an obvious cause for an observed or reported concern found?
Yes Correct the cause as necessary. No GO to A2 - A2 CHECK THE AUXILIARY SYSTEM
- Ignition ON.
- Operate all the upfitter accessories.
Are all the upfitter accessories inoperative?
Yes GO to A3 No GO to A6 - A3 CHECK FOR VOLTAGE TO THE AUXILIARY SWITCH
- Ignition OFF.
- Disconnect Upfitter switch C9120.
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead Refer to C9120-5 Ground Refer to C9120-11 Ground
Is the voltage greater than 11 volts?
Yes GO to A4 No REPAIR the affected circuit for an open. - A4 CHECK FOR VOLTAGE TO THE UPFITTER RELAY BOX
- Ignition OFF.
- Measure:
Positive Lead Measurement / Action Negative Lead Refer to C3271A-1 Ground
Is the voltage greater than 11 volts?
Yes GO to A7 No REPAIR the affected circuit. - A5 CHECK FOR GROUND TO THE UPFITTER RELAY BOX
- Remove upfitter relays 1 through 6.
- Measure: For relay and pin assignments, Refer to Fuse and Relay Information
for schematic and connector information.
Positive Lead Measurement / Action Negative Lead Upfitter Relay 1, Pin 2 Ground Upfitter Relay 2, Pin 2 Ground Upfitter Relay 3, Pin 2 Ground Upfitter Relay 4, Pin 2 Ground Upfitter Relay 5, Pin 2 Ground Upfitter Relay 6, Pin 2 Ground
Is the resistance less than 3 ohms?
Yes INSTALL an new upfitter relay box. No REPAIR the circuit in question for an open. - A6 CHECK THE UPFITTER RELAY
- Ignition OFF.
- Substitute suspect upfitter relay with a known good relay.
- Ignition ON.
- Place the upfitter switch in question to the ON position.
Does the upfitter accessory operate?
Yes INSTALL a new upfitter relay. No REMOVE the known good relay. GO to A7 - A7 BYPASS THE UPFITTER RELAY
- Ignition OFF.
- Disconnect Suspect upfitter relay.
- For the upfitter system in question, connect a fused jumper wire: For relay and pin assignments, Refer to Fuse and Relay Information
for schematic and connector information.
Positive Lead Measurement / Action Negative Lead Upfitter Relay Pin 3 Upfitter Relay Pin 5
Did the upfitter accessory operate?
Yes REMOVE the jumper wire. Go to A9 No REMOVE the jumper wire. Go to A8 - A8 CHECK UPFITTER RELAY SUPPLY VOLTAGE
- For the auxiliary switch in question, measure: For relay and pin assignments, Refer to Fuse and Relay Information
for schematic and connector information. for schematic and connector information.
Positive Lead Measurement / Action Negative Lead Upfitter Relay Pin 3 Ground
Is the voltage greater than 11 volts?
Yes GO to A9 No REPAIR the circuit in question for an open. - For the auxiliary switch in question, measure: For relay and pin assignments, Refer to Fuse and Relay Information
for schematic and connector information. for schematic and connector information.
- A9 CHECK THE UPFITTER RELAY GROUND CIRCUITS
- For the auxiliary switch in question, measure: For relay and pin assignments, Refer to Fuse and Relay Information
for schematic and connector information.
Positive Lead Measurement / Action Negative Lead Upfitter Relay Pin 2 Ground
Is the resistance less than 3 ohms?
Yes GO to A10 No REPAIR the upfitter relay ground circuit in question for an open. - For the auxiliary switch in question, measure: For relay and pin assignments, Refer to Fuse and Relay Information
for schematic and connector information.
- A10 CHECK THE UPFITTER RELAY CONTROL CIRCUIT FOR OPEN
- Turn the auxiliary switch for the circuit in question ON.
- For the auxiliary switch in question, measure: For relay and pin assignments, Refer to Fuse and Relay Information
for schematic and connector information.
Positive Lead Measurement / Action Negative Lead Upfitter relay pin 1 Ground
Is the voltage greater than 11 volts?
Yes The system is operating correctly at this time. The concern may have been caused by loose or intermittent module connections. VERIFY customer concern and ADDRESS the root cause of any connector or pin issues. No REPAIR the circuit in question for an open.