Passat Sedan L4-1781cc 1.8L Turbo (AEB) (1999)
Coolant Temperature Sensor/Switch (For Computer): Testing and Inspection
Engine Coolant Temperature sensor, checking
Special tools, testers, measuring instruments and auxiliary items required
-
VAG 1551/1552 Scan Tool with VAG 1551/3B adaptor cable
-
VAG 1598/22 Test Box
-
Fluke 83 Multimeter
-
VW 1594 Adaptor kit
-
Wiring diagram
NOTE:
The Engine Control Module will use the Intake Air Temperature as a replacement value for an engine start (start temperature replacement value) as soon
as there is a DTC stored in DTC memory, which affects the Engine Coolant Temperature sensor G62. The temperature then rises using a model stored in
the Control Module. When the engine has reached normal working temperature a fixed replacement value will be displayed after a certain period. This
fixed value is also dependent upon the Intake Air Temperature.
Test conditions
-
Engine must be cold.
Test sequence
-
Connect VAG 1551/1552 Scan Tool, See: Powertrain Management/Computers and Control Systems/Testing and Inspection/Reading and Clearing
Diagnostic Trouble Codes/Scan Tool Connecting
-
Switch ON ignition
-
Press 0 and 1 buttons to select "Address word" 01 "Engine electronics"
Display will appear as shown
Rapid data transfer
HELP
Select function XX
-
Press 0 and 8 buttons to select Function 08: "Read measuring value block"
-
Press Q button to enter input
Display will appear as shown
Read measuring value block
HELP
Input Display group number XXX
-
Press 0, 0 and 1 buttons to select "Display group 1"
-
Press Q button to enter input
Display will appear as shown (1 to 4 = Display zones)
Read measuring value block 1 ->
1
2
3
4
-
Check the specification for Engine Coolant Temperature sensor in Display zone 2, chart.