Self-Test, Performing
Before the leak test, clean the Cooling System Tester - Directional Valve: VAS691005/1 as follows:
-- Attach the cleaning nozzle to the connection "A" for the Digital Pressure Sensor: VAG1397B .
-- Attach the pressure hose to the connection "C" on the Cooling System Tester - Directional Valve: VAS691005/1 .
-- Open the shut-off valves "A" and "C" on the Cooling System Tester - Directional Valve: VAS691005/1 .
-- Clean the Cooling System Tester - Directional Valve: VAS691005/1 with compressed air.
-- Remove the cleaning nozzle from the connection "A" on the Cooling System Tester - Directional Valve: VAS691005/1 .
-- Connect the connection "A" on the Cooling System Tester - Directional Valve: VAS691005/1 to the connection "II" on the Digital Pressure Sensor: VAG1397B .
-- Connect the Cooling System Tester: VAG1274B to the connection "C" on the Cooling System Tester - Directional Valve: VAS691005/1 .
-- Open the shut-off valves "A" and "C" on the Cooling System Tester - Directional Valve: VAS691005/1 .
-- Switch on the Digital Pressure Sensor: VAG1397B and select setting "II".
-- Create pressure using the Cooling System Tester - Hand Pump: VAG1274B until approximately 2.5 bar (36.26 psi) appears on the Digital Pressure Sensor: VAG1397B
-- Check the loss of pressure on the Digital Pressure Sensor: VAG1397B after approximately one minute of wait time (settling).
If no loss of pressure is detected on the Digital Pressure Sensor: VAG1397B , then the Cooling System Tester for High Voltage Batteries: VAS691005 is OK.
Test Requirements
- The coolant temperature in the cooling system for the high-voltage system must be at room temperature; if necessary let the vehicle "acclimate" in the workshop for 60 minutes.
- The Test Set: VAS691005 self-test was performed, and the Test Set: VAS691005 must be OK. Refer to Self-Test, Performing .
- Ignition off.
Test Sequence
There is a risk of explosion caused by cooling system leaks in the high-voltage battery. This can cause a buildup of explosive gases in the battery housing.
Explosions may cause severe bodily injuries.
- Do not add coolant when the coolant level is low in the coolant expansion tank, until the cause of the leak is corrected.
- If the indicator lamps for "low coolant" and "high-voltage battery error" turn on, move the vehicle outdoors to the specified separate parking area.
- Notify the high-voltage experts for the importer.
-- Cut the tab on the seal -3- and open the coolant expansion tank cap -1- for the high-voltage system cooling circuit (example illustration).
-- Check the coolant level in the coolant expansion tank.
-- If there is no coolant present in the coolant expansion tank, then check for leaks in the High-Voltage Battery. Refer to HIGH-VOLTAGE BATTERY LEAK DETECTION .
-- If there is a residual amount of coolant in the coolant expansion tank, then fill coolant up to the "Max" mark.
-- Connect the Cooling System Tester - Directional Valve: VAS691005/1 :
- Connection "A" to the connection "II" on the Digital Pressure Sensor: VAG1397B .
- Connection "B" on the Cooling System Tester - Directional Valve: VAS691005/5 on the coolant expansion tank -1- (example illustration).
- Connection "C" to the Cooling System Tester : VAG1274B .
-- Open the shut-off valves "A" and "C" on the Cooling System Tester - Directional Valve: VAS691005/1 .
-- Switch on the Digital Pressure Sensor: VAG1397B and select setting "II".
-- Create pressure using the Cooling System Tester - Hand Pump: VAG1274B until approximately 2 bar (29.01 psi) appears on the Digital Pressure Sensor: VAG1397B
-- Connect the shut-off valve "C" to the Cooling System Tester - Directional Valve: VAS691005/1 .
-- Note the value displayed on the Digital Pressure Sensor: VAG1397B .
-- Check the pressure decrease on the Digital Pressure Sensor: VAG1397B after a 10 minute wait time (settling).
- The loss of pressure must not exceed a maximum of 0.2 bar (2.9 psi).
If the loss of pressure is over 0.2 bar (2.9 psi) (leak is suspected):
-- Switch the ignition on.
-- Check the indicator lamps in the instrument cluster.
-- If the "coolant quantity" and an "error in the high-voltage battery" is not displayed, check for leaks in the high-voltage battery. Refer to HIGH-VOLTAGE BATTERY LEAK DETECTION .
If the loss of pressure is under 0.2 bar:
-- Note the current value displayed on the Digital Pressure Sensor: VAG1397B .
-- Check the pressure decrease on the Turbocharger Tester Kit: VAG1397A after waiting another 10 minutes.
- The loss of pressure now must not exceed a maximum of 0.02 bar (0.29 psi).
If the loss of pressure is over 0.02 bar (0.29 psi) (leak is suspected):
-- Connect the shut-off valve "A" to the Cooling System Tester - Directional Valve: VAS691005/1 .
-- Disconnect the Turbocharger Tester Kit: VAG1397A and Cooling System Tester: VAG1274B from the Cooling System Tester - Directional Valve: VAS691005/1 .
-- To reduce the pressure, slowly open the shut-off valve "C" on the Cooling System Tester - Directional Valve: VAS691005/1 and catch any leaking coolant using a suitable container.
-- Disconnect the Cooling System Tester - Directional Valve: VAS691005/1 from the Cooling System Tester - Directional Valve: VAS691005/5 on the coolant expansion tank -1-.
-- Remove the Cooling System Tester - Directional Valve: VAS691005/5 from the coolant expansion tank.
-- Check the high-voltage battery for leaks. Refer to HIGH-VOLTAGE BATTERY LEAK DETECTION .
If the loss of pressure is under 0.02 bar (0.29 psi) (cooling system is OK):
-- Connect the shut-off valve "A" to the Cooling System Tester - Directional Valve: VAS691005/1 .
-- Disconnect the Turbocharger Tester Kit: VAG1397A and Cooling System Tester: VAG1274B from the Cooling System Tester - Directional Valve: VAS691005/1 .
-- To reduce the pressure, slowly open the shut-off valve "C" on the Cooling System Tester - Directional Valve: VAS691005/1 and catch any leaking coolant on the Cooling System Tester - Directional Valve: VAS691005/1 using a suitable container.
-- Disconnect the Cooling System Tester - Directional Valve: VAS691005/1 from the Cooling System Tester - Directional Valve: VAS691005/5 on the coolant expansion tank -1-.
-- Remove the Cooling System Tester - Directional Valve: VAS691005/5 from the coolant expansion tank.
-- Add the coolant. Refer to COOLANT, ADDING AND COOLING SYSTEM, BLEEDING, HIGH-VOLTAGE SYSTEM COOLING CIRCUIT .