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Home >> Volkswagen >> 2000 >> Jetta GL, 1.9 F, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> 1.9L - Fuel Injection Glow Plug, Engine Code: ALH (A4 Platform) >> 23 Diesel Fuel Injection >> Diesel fuel injection components and functions, checking >> Engine Coolant Temperature (ECT) sensor, checking >> Test sequence
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Test sequence

Indicated on display

Rapid data transfer HELP
Select function XX

Indicated on display

Read measured value block HELP
Input display group number XXX
Read measured value block 7 ->
15.4 ° C 15.9 ° C 16.7 ° C

In the case of a malfunction the fuel temperature is displayed as a substitute.

If the display in field 4 appears unrealistic or the fuel temperature is displayed as a substitute, check the ECT sensor and wiring connections to the sensor as follows:

Fig 1: ECT Sensor
GW00001078Courtesy of VOLKSWAGEN UNITED STATES, INC.
Fig 2: Engine Coolant Temperature Sensor G62 Terminals 1 & 3
GW00001079Courtesy of VOLKSWAGEN UNITED STATES, INC.
Fig 3: Resistance Values Graph
GW00001080Courtesy of VOLKSWAGEN UNITED STATES, INC.
NOTE:
  • Scale A shows resistance values for temperature range 0 to 50 ° C and scale B shows the values for temperature range 50 to 100 ° C.

Examples:

If specification is not obtained:

If DTC memory has been erased, the readiness code must be generated again → Readiness code, setting  .

If specification is obtained:

Fig 4: Identifying Test Box V.A.G 1598/22 Connected To Control Module Wiring Harness
GW00000771Courtesy of VOLKSWAGEN UNITED STATES, INC.
Fig 5: Identifying Harness Connector Terminals 1 & 3
GW00001081Courtesy of VOLKSWAGEN UNITED STATES, INC.
  Test box socket no.
Terminal Through MY 1999 From MY 2000
1 70 -
3 54 112
4 - 104