Tesla Model S: Forward Junction Box - 2nd Generation (Remove and Replace)
Warning: Only technicians who have been trained in High
Voltage Awareness are permitted to perform this procedure. Proper
personal protective equipment (PPE) and insulating HV gloves with a
minimum rating of class 00 (500V) must be worn any time a high
voltage cable is handled. Refer to Tech Note TN-15-92-003, "High
Voltage Awareness Care Points" for additional safety information.
This procedure only applies to vehicles with the 2nd generation High
Voltage configuration. The Forward Junction Box is part of the DCDC
converter for vehicles with the 1st generation High Voltage
Configuration.
Removal
- Perform the vehicle electrical isolation procedure (refer
to procedure).
- Remove the extension box from the underhood storage compartment
(refer to procedure).
- Release the 4 harnesses from the top of the FJB.
1
|
HV Battery heater
harness |
2
|
DCDC converter harness |
3
|
Compressor harness |
4
|
PTC heater harness |
- Release the 12V harness from the left side of the FJB.
- Release the 6 bolts that secure the FJB cover (torque 7 Nm).
Remove the cover.
Warning: Before continuing, put on high voltage gloves.
- Use a small, insulated screwdriver or similar tool to pry open
the cover on the front upper left of the FJB.
Warning: Do not use a metallic tool to open the
cover.
- Use a multimeter to check voltages between:
- B+ to ground
- B- to ground
- B+ and B-
Warning: If any voltage reading is more than 10V,
the high voltage contactors are not fully opened. Due to the
risk of electrocution, contact Service Engineering before
performing any further work.
- Release the 2 bolts that secure the HV cables to the busbars
inside the FJB (torque 4 Nm).
- Release the clips that secure the HV cables.
Note: The O-rings on the HV cables might create
suction, which makes the cables difficult to remove. It
might require greater than normal force to release the
cables.
- Release the 3 bolts that secure the FJB to the body (torque 10
Nm). Carefully remove the FJB.
InstallationInstallation procedure is the reverse of removal.
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Warning: Only technicians who have been trained in High
Voltage Awareness are permitted to perform this procedure. Proper
personal protective equipment (PPE) and insulating HV gloves with a
Warning: Only technicians who have been trained in High
Voltage Awareness are permitted to perform this procedure. Proper
personal protective equipment (PPE) and insulating HV gloves with a
Warning: Only technicians who have been trained in High
Voltage Awareness are permitted to perform this procedure. Proper
personal protective equipment (PPE) and insulating HV gloves with a
SEE MORE:
Use brake cleaner to clean the threaded rod and the nut bearing
assemblies.
Use 3M Spray Lube 08878 or equivalent to lubricate the threaded
rod and the nut bearing assemblies.
Slide the bushing into the left side of the front motor mount so
that the shorter cavities are horiz
Removal
Open liftgate.
Support liftgate in open position.
Release clip securing gas strut to body.
Disconnect gas strut from ball joint.
Release clip securing gas strut to liftgate.
Disconnect and remove gas