Check wiring and connections between the EST::ECU (E112) and EST::MPU::eMotor (M53). 1. Check power supply connection for corrosion: - Switch battery OFF - Remove MPU pole cover - Thoroughly inspect the plus pole cable ring terminal, the associated M6 nut, and the cable wire where it is crimped to the ring terminal, for corrosion. >> If corroded, the ring terminal, nut and wire/cable, must be replaced as a set. >> If the terminal screw on the MPU::eMotor is badly corroded, the eMotor must be replaced as well. 2. Check power supply to MPU: - Remove MPU pole cover - Switch battery ON (connections / master switch) and measure voltage on MPU power terminals (M6 screws). It should be approximately 24 volt (battery voltage). - Switch battery OFF - Check tightening torque for both M6 terminal nuts, and ground cable connection to frame. - Check the MPU fuse - Visually inspect the isolation along the entire cable length, for abrasion damage that could lead to a short circuit against frame or similar. 3. Check wake-up cable harness and connectors: - Switch battery OFF - Disconnect harness connector on both ECU side, and MPU side. - Measure the resistance in the cable between pins E112::A34 and M53::C3. It should be aproximately 0 ohm (no interruption or bad connection). - Visually inspect the isolation along the entire cable length, for abrasion damage that could lead to a short circuit against frame or similar. 4. Check CAN cable harness and connectors: - Switch battery OFF - Disconnect harness connectors on both ECU side, and MPU side. - Measure the resistance in the cable between pins E112::A11 and M53::C4. It should be approximately 0 ohm (no interruption or bad connection). - Measure the resistance in the cable between pins E112::A14 and M53::C2. It should be approximately 0 ohm (no interruption or bad connection). - Measure the resistance in the cable between each single wire. It should be infinite (no short circuit). - Visually inspect the isolation along the entire cable length, for abrasion damage that could lead to a short circuit against frame or similar. 5. Check MPU and ECU: - Switch battery OFF - Disconnect harness connector only on ECU side, and measure the resistance between pins E112::A11 and E112::A14. It should be approximately 120 ohm (termination resistor in MPU). - Reconnect ECU connector - Disconnect harness connector only on MPU side, and measure the resistance between pins M53::C2 and M53::C4. It should be approximately 120 ohm (termination resistor in ECU). - Reconnect MPU connector Verify that the issue is solved by performing a Diagnostic SelfTest (requires Parking Brake to be applied) - If the root cause fault has been fixed, this DTC will be set passive.

Diagnostic depth