CLAAS Id7645h / 7645h (438) – TR2 (A57-2) Auto 5 module: Voltage Detected on SV3 Solenoid Valve Circuit When Commanded Off

A supply voltage is being measured on the circuit for solenoid valve SV3 when the driver (the ECU output) is not actively commanding it to operate (setpoint PWM = 0). This typically points to a 12V short circuit in the wiring harness or an internal fault within the control module.

• CLAAS Axion 800 Series (810, 850)
• CLAAS Arion 600 Series (610, 620, 630, 640, 650)
• CLAAS Arion 500 Series (510, 530, 550)

1. 1

   Check for a possible 12 V short circuit on the solenoid valve power supply harness leading to the SV3 valve (Component designation: Y335-3).

2. 2

   Check the Auto 5 module (TR2 / A57-2) using the official CLAAS diagnostic breakout tool (Tool No. 60 05 033 249) to determine if the module itself is internally shorted and sending voltage inappropriately.

1. 1

   Locate the Component

   Identify the SV3 solenoid valve (Y335-3), which is designated as the 'Ratio under torque solenoid valve (SV3)' on the transmission hydraulic block.

2. 2

   Inspect Wiring

   Trace the wiring harness from the SV3 solenoid valve back to the TR2 (A57-2) 'Auto 5' module. Look for chafed wires, melted insulation, or pinched harnesses that could be bridging the SV3 circuit to a constant 12V power source.

3. 3

   Repair Wiring

   If a short to 12V is found in the harness, repair the damaged wiring or replace the affected harness section.

4. 4

   Test the ECU

   If the wiring harness tests perfectly fine (no shorts to power), connect CLAAS diagnostic tool 60 05 033 249 to the 'Auto 5' module to verify its integrity.

5. 5

   Replace ECU (if necessary)

   If the module fails the diagnostic test and is proven to be leaking voltage to the SV3 circuit internally, replace the 'Auto 5' module.

6. 6

   Reset

   Perform the requested 'ISC' reset and clear the fault codes to verify the repair.