2026-07-23

HV Harness - Rear Drive Unit - RH (Tri Motor) (Remove and Replace)

Correction code 4450074092 FRT 2.88 NOTE: Unless otherwise explicitly stated in the procedure, the correction code and FRT listed above reflect all of the work required to perform this procedure, including the linked procedures. Do not stack correction codes unless explicitly told to do so. NOTE: See Flat Rate Times to learn more about FRTs and how they are created. NOTE: See Personal Protection to make sure you are wearing proper PPE when performing the procedure below. NOTE: See Ergonomic Precautions for safe and healthy working practices.

Warning

This procedure is a DRAFT. Although it has been validated, Warnings and Cautions might be missing. Follow safety requirements and use extreme caution when working on or near High Voltage systems and components.

Warning

Cybertruck electronics are powered by a 48V "mid voltage" or "MV" architecture that is designed to improve efficiency. Servicing MV components requires extra knowledge and care in order to avoid personal and/or vehicular harm. Read and understand MV precautions in Electrical Precautions and make sure any required MV-related training courses have been completed, as applicable.

Warning

Only technicians who have been trained in High Voltage Awareness and have completed all required certification courses (if applicable) are permitted to perform this procedure. Proper personal protective equipment (PPE) and insulating HV gloves with a minimum rating of class 0 (1000V) must be worn at all times a high voltage cable, busbar, or fitting is handled. Refer to Tech Note TN-15-92-003, High Voltage Awareness Care Points for additional glove and safety information.

Open the LH front door and lower the LH front window.
Open the powered frunk.
Raise and support the vehicle. See Raise Vehicle - 2 Post Lift.
Place the vehicle into Service Mode. See Service Mode.
Unlock the vehicle Gateway. See Gateway (Unlock).
Access thermal system routines using the UI

Note
Select quick controls > Service mode > Diagnostics > Thermal, Authorize routines by holding right turn signal, depressing brake pedal for 10 seconds with key on phone dock
Select 'Coolant System' to enter coolant circuit screen, Select 'Coolant Fill/Drain' using the UI and
PROC_VCFRONT_X_START-THERMAL-FILL-DRAIN
via Service Mode:
Thermal ➜ Actions ➜ Start Thermal Fill/Drain
Thermal ➜ Coolant System ➜ Start Coolant Fill/Drain
Thermal ➜ Refrigerant System ➜ Start Refrigerant Fill/Drain
via Service Mode Plus:
Drive Inverter ➜ Front Drive Inverter Replacement ➜ Start Fluid Fill/Drain
Drive Inverter ➜ Rear Drive Inverter Replacement ➜ Start Fluid Fill/Drain
Drive Unit ➜ Front Drive Unit Replacement ➜ Start Coolant Fill/Drain
Drive Unit ➜ Rear Drive Unit Replacement ➜ Start Coolant Fill/Drain
via Toolbox:(link)
-COOLANT window will appear, Select 'Run'
Note
Verify indicator displays green for Coolant readiness, Thermal Fill Drain routine has a 50 minute time limit
Connect a laptop with Toolbox to the vehicle. See Toolbox 3 (Connect and Disconnect).
Select "Actions" and search for "EPB"
Select
PROC_EPB_X_SERVICE-MODE
via Service Mode:
Chassis ➜ Brakes ➜ EPB Service Mode
Chassis ➜ Brakes ➜ EPB Service Mode
via Service Mode Plus:Drive Unit ➜ Rear Drive Unit Replacement ➜ Release / Re-Engage Emergency Parking Brakevia Toolbox:(link)
, click 'Run', and allow routine to complete
Note
Choose 'BOTH' under "EPB Selection", Choose 'START' under "Action Selection", Chock wheel if necessary, Select ‘X’ at top right of window to close once complete
Remove the rear underhood apron. See Underhood Apron - Rear (Remove and Install).
Disconnect MV power. See Mid-Voltage Power (Disconnect and Connect) (Modify).
Remove the LH and RH rear wheels. See Wheel Assembly (Remove and Install).
Disconnect RH rear EPB harness

Note
1x connector, Release locking tab
Release RH rear brake line from upper control arm

Note
1x bolt, 10mm, 10 Nm
Remove RH rear brake caliper and set aside

Note
2x bolts, 21 mm, 150 Nm, Hang caliper from body if not fully removing, Route caliper hose so that it does not get caught on stabar assembly
Remove RH rear brake rotor

Note
Rotor will be loose until caliper is installed
Use jack to simulate ride height on RH rear suspension

Note
Raise jack to simulate ride height, This is to release tension from the upper control arm which will be removed next later steps, DO NOT skip this you run into the risk of hurting yourself
Remove RH rear toe link from RH rear knuckle

Note
1x nut, 21mm, 170 Nm, Counter hold ball joint, Discard nyloc nut after removal
Remove nut securing RH rear upper control arm to knuckle

Note
1x nylon nut, 21 mm, 150 Nm, Discard nut after removal, Place support stand below suspension to ease removal
Use jack to lower RH rear ride height back to hanging position

Note
Lower jack to let suspension hang
Release harness from RH rear air spring module

Note
2x connectors, 1x grommet
Remove RH rear lower control arm aeroshield

Note
3x bolts, 10mm, 7 Nm
Remove nuts securing RH rear air spring module to lower control arm

Note
2x nylon nut, 21 mm, 140 Nm, Discard nuts after removal
Disconnect EPB harness connector from LH rear brake caliper

Note
1x connector, Release locking tab
Release LH rear brake line from upper control arm

Note
1x bolt, 10mm, 10 Nm
Remove LH rear brake caliper and set aside

Note
2x bolts, 21 mm, 150 Nm, Hang caliper from body if not fully removing, Route caliper hose so that it does not get caught on stabar assembly
Remove LH rear brake rotor

Note
Rotor will be loose until caliper is installed
Use jack to simulate ride height on LH rear suspension

Note
Raise jack to simulate ride height, This is to release tension from the upper control arm which will be removed next later steps, DO NOT skip this you run into the risk of hurting yourself
Remove LH rear toe link from LH rear knuckle

Note
1x nut, 21mm, 170 Nm, Counter hold ball joint, Discard nyloc nut after removal
Remove nut securing LH rear upper control arm to knuckle

Note
1x nylon nut, 21 mm, 150 Nm, Discard nut after removal, Move brake hose aside to avoid damage, Use caution when releasing rear upper control from knuckle
Use jack to lower LH rear ride height back to hanging position

Note
Lower jack to let suspension hang
Release harness from LH rear air spring module

Note
2x connectors, 1x grommet
Remove LH rear lower control arm aeroshield

Note
3x bolts, 10mm, 7 Nm
Remove nuts securing LH rear air spring module to lower control arm

Note
2x nylon nut, 21 mm, 140 Nm, Discard nuts after removal
Remove rear skid plate. See Skid Plate - Rear (Remove and Install).
Remove the rear aeroshield. See Aeroshield - Rear (Remove and Install).
Remove the rear diffuser. See Diffuser - Rear (Remove and Install).
Remove all items from pockets and ensure not wearing metal items
Inspect HV insulating gloves

Note
Check gloves for damage prior to use, Refer to service document TN-15-92-003, for information on inspecting HV gloves.
Put on HV insulating gloves and leather over gloves
Remove clips securing AC compressor HV harness

Note
3x clips
Verify no HV - Install amp clamp to RDU HV harness

Note
Verify meter is zeroed out before performing measurement, Measure single cable. Verify ammeter is installed in correct direction. If current > 0.5A do not proceed with disconnecting HV connector. In this case, start vehicle electrical isolation again to make sure that all was properly shut down. Escalate for assistance as required. If current < 0.5A, Ok to disconnect and check voltage at HV plug on the battery side. Release locking tab and rotate the release lever up to disengage the connector, Release harness clip, Do not force the release lever up, Ensure the alignment tabs on the RDU header are not damaged. Make sure to wear PPE (HV gloves, safety glasses) when working on high voltage component, Measure B+ to Ground, B- to Ground, B+ to B-, If voltage is greater than 10V, Pack contactors are not open or welded, Stop work and reach out to Service Engineering
Disconnect RDU HV harness

Note
1x connector, Release locking tab and rotate release lever up, Do not force release lever up, Ensure alignment tabs on header are not damaged
Remove leather over gloves and HV insulating gloves
Position coolant drain container underneath RH rear of HV battery
Remove front lower clips securing RH rear wheel arch liner

Note
3x clips
Disconnect RDU return hose from PT return hose

Note
1x spring clip, 1x clamp clip, Move wheel liner aside as needed, Plug coolant connections as needed
Disconnect RDU supply hose from HV battery

Note
1x spring clip, Plug coolant connections as needed
Remove coolant drain container from underneath vehicle
Disconnect rear steering gear harness from subframe

Note
1x connector, Release red locking tab
Disconnect rear subframe harness from rear fascia harness

Note
3x connectors
Release rear diffuser brackets and set aside

Note
6x bolts, 13mm, 30 Nm, 4x tabs, Let brackets hang
Lower vehicle partially and set lift onto locks

Note
Raise lift off locks, then hold lock release lever to keep locks free while vehicle is lowered, Set vehicle to comfortable working height
Position powertrain lift under rear subframe
Connect shop air supply to powertrain table
Raise powertrain lift to rear subframe

Note
Make sure the height setting of the hoist can be reached with the powertrain lift height limit
Safely secure rear subframe onto powertrain lift

Note
Secure subframe to powertrain table and fixture
Remove bolts securing rear subframe to body

Note
4x bolts, 24mm, 355 Nm
Lower subframe table to access breather tube

Note
Use caution with RDU coolant hoses and breather line, Subframe jig assembly will need to be maneuvered to prevent coolant lines getting caught, Access breather from LH rear wheel well
Disconnect RDU breather tube

Note
2x tabs, 1x clip, Press tabs inward and pull breather up, Release clip from RDU casing
Fully lower subframe table

Note
Use caution with RDU coolant hoses, Subframe table will need to be moved back to prevent coolant lines getting caught, Ensure DU breather line is not caught
Disconnect air supply from subframe lifting tool
Remove RH RDU inverter to chiller hose

Note
2x spring clips, Plug coolant connections as needed
Remove clip securing RSA jumper harness to RHS RDU HV harness

Note
1x clip
Disconnect RHS RDU harness

Note
1x connector, Release locking tab and rotate release lever up, Do not force release lever up, Ensure alignment tabs on header are not damaged
Remove RHS RDU harness

Note
5x bolts, 10mm, 12 Nm
Install RHS RDU harness

Note
5x bolts, 10mm, 12 Nm
Connect RHS RDU harness

Note
1x connector, Verify lever is upright and in open position, Carefully seat connector and allow lever to engage, Fully secure lever and verify red tab is locked, Do not damage any pins
Install clip securing RSA jumper harness to RHS RDU HV harness

Note
1x clip
Install RH RDU inverter to chiller hose

Note
2x spring clips, Remove plugs as needed
Position subframe lifting tool with subframe assembly under vehicle
Connect air supply to subframe lifting tool
Raise drive unit until sufficient access is available to breather

Note
Recommend assistance, Use caution to not damage components while raising subframe, Position coolant lines above HV battery lip
Connect RDU breather tube

Note
2x tabs, 1x clip, Install clip onto RDU casing, Verify tabs are fully engaged
Fully raise rear drive unit and subframe into position

Note
Recommend assistance, Use caution to not damage components while raising subframe, Position coolant lines above HV battery lip
Loosely install bolts securing rear subframe to body

Note
4x bolts, 24mm, Hand Tight, Start bolts by hand before using power tools
Torque rear subframe bolts

Note
4x bolts, 24mm, 355 Nm
Remove rear subframe tie downs from powertrain lift

Note
Release subframe to powertrain table and fixture
Lower powertrain table from subframe and move away from vehicle
Secure rear diffuser brackets

Note
6x bolts, 13mm, 30 Nm, 4 tabs
Connect tri motor rear subframe harness onto rear fascia harness

Note
3x connectors
Connect rear steering gear harness

Note
1x connector, Engage red locking tab
Position coolant drain container underneath RH rear of HV battery
Connect RDU supply hose onto HV battery

Note
1x spring clip, Remove plugs as needed
Connect RDU return hose to PT return hose

Note
1x spring clip, 1x clamp clip, Move wheel liner aside as needed, Remove plugs
Install front lower clips securing RH rear wheel arch liner

Note
3x clips
Remove coolant drain container from underneath vehicle
Connect RDU HV harness

Note
1x connector, Verify lever is upright and in open position, Carefully seat connector and allow lever to engage, Fully secure lever and verify red tab is locked, Do not damage any pins
Connect LHS RDU HV harness

Note
1x connector, Verify lever is upright and in open position, Carefully seat connector and allow lever to engage, Fully secure lever and verify red tab is locked, Do not damage any pins
Install clips securing AC compressor HV harness

Note
3x clips
Install the rear diffuser. See Diffuser - Rear (Remove and Install).
Install the rear aeroshield. See Aeroshield - Rear (Remove and Install).
Install rear skid plate. See Skid Plate - Rear (Remove and Install).
Lower vehicle partially and set lift onto locks

Note
Raise lift off locks, then hold lock release lever to keep locks free while vehicle is lowered, Set vehicle to comfortable working height
Install nuts securing LH rear air spring module to lower control arm assembly

Note
2x nylon nut, 21 mm, 140 Nm, Install new nylon nuts
Install LH rear lower control arm aeroshield

Note
3x bolts, 10mm, 7 Nm
Secure harness to LH rear active dampener

Note
2x connectors, 2x grommets
Install nut securing LH rear upper control arm to knuckle

Note
1x nylon nut, 21 mm, 150 Nm, Install new nylon nut, Counter-hold joint to install nut, Support suspension to ease installation, Ensure brake hose is properly routed
Install LH rear toe link onto LH rear knuckle

Note
1x nut, 21mm, 170 Nm, Install new Nyloc nut
Install LH rear brake caliper onto LH rear knuckle

Note
2x bolts, 21mm, 150 Nm
Connect EPB harness connector to LH rear brake caliper

Note
1x connector, Engage locking tab
Install LH rear brake line onto upper control arm

Note
1x bolt, 10 mm, 10 Nm
Install nuts securing RH rear air spring module to lower control arm assembly

Note
2x nylon nut, 21 mm, 140 Nm, Install new nylon nuts
Install RH rear lower control arm aeroshield

Note
3x bolts, 10mm, 7 Nm
Secure harness to RH rear active dampener

Note
2x connectors, 2x grommets
Install nut securing RH rear upper control arm to knuckle

Note
1x nylon nut, 21 mm, 150 Nm, Install new nylon nut, Counter-hold joint to install nut, Support suspension to ease installation
Install RH rear toe link onto RH rear knuckle

Note
1x nut, 21mm, 170 Nm, Install new Nyloc nut
Install RH rear brake caliper onto RH rear knuckle

Note
2x bolts, 21mm, 150 Nm
Connect RH rear EPB harness

Note
1x connector, Engage locking tab
Install RH rear brake line onto upper control arm

Note
1x bolt, 10 mm, 10 Nm
Install the LH and RH rear wheels. See Wheel Assembly (Remove and Install).
Perform cooling system vacuum refill. See Cooling System (Vacuum Refill).
Install the rear underhood apron. See Underhood Apron - Rear (Remove and Install).
Remove the vehicle from the lift. See Raise Vehicle - 2 Post Lift.
Raise the LH front window and close the LH front door.

Cybertruck Service Manual

HV Harness - Rear Drive Unit - RH (Tri Motor) (Remove and Replace)

Figure 1

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Figure 3