Auto-Check System, Troubleshooting
General notes
- For instrument cluster and instrument cluster component removing and installing procedures INSTRUMENT CLUSTER
- For locations of Auto-Check system components in engine compartment ELECTRICAL SYSTEM COMPONENTS
If all specified values are obtained during troubleshooting and Auto Check system continues to malfunction:
-- Replace Auto-Check system/trip computer printed circuit board.
If incorrectly formed symbols or lines appear on display:
-- Replace Auto-Check system/trip computer display module.
Before replacing a faulty component:
-- Check wiring to component for open/short circuits according to wiring diagram, repair as necessary.
If Auto-Check system display is dim:
-- Check bulbs INSTRUMENT CLUSTER BULBS
Test conditions
- Battery OK
- Fuse -S8- OK
- Fuse -S15- OK
- Auto-Check system coding switch set properly Checking
- Voltage stabilizer OK (checking VOLTAGE STABILIZER AND FUEL GAUGE, CHECKING
- Use digital multimeter (Fluke 83 or equivalent), connector test kit VW 1594, VAG 1598 test box, adapter: VAG1598/4 cable and : VAG1598/20 test adapter when performing electrical checks
- Always refer to appropriate wiring diagram when troubleshooting
NOTE:
If available, use adapter cable: VAG1598/13 in place of : VAG1598/20 test adapter.
| Test measurement at red 26-point instrument cluster connector | Additional steps | Specified reading | Action if specified reading not obtained |
|---|---|---|---|
| -- Connect adapter: VAG1598/4 cable to red 26-point instrument cluster connector | -- Connect other end of adapter: VAG1598/4 cable to instrument cluster | ||
| Voltage supply | |||
| -- Set multimeter (Fluke 83 or equivalent) to volt range-- Connect multimeter red test lead to socket 11 and black test lead to socket 10 of VAG 1598 test box | -- Switch ignition ON |
|
-- Check for open circuit in wiring according to wiring diagram, repair as necessary |
| -- Connect multimeter red test lead to socket 14 and black test lead to socket 10 of VAG 1598 test box |
|
-- Check for open circuit in wiring according to wiring diagram, repair as necessary | |
| Display unit illumination | |||
| -- Set multimeter to volt range-- Connect multimeter black test lead to socket 10 and red test lead to socket 22 of VAG 1598 test box | -- Switch parking lights ON |
|
-- Check for open circuit in wiring according to wiring diagram, repair as necessary |
| Fuel gauge | |||
| -- Switch ignition OFF-- Disconnect adapter: VAG1598/4 cable from instrument cluster-- Set multimeter to measure resistance (Ω)-- Connect multimeter between sockets 3 and 10 of VAG 1598 test box |
|
-- Check for open circuit in wiring according to wiring diagram, repair as necessary, or-- Replace fuel level sensor | |
| -- Connect adapter: VAG1598/4 cable to red 26-point instrument cluster connector |
| Brake fluid level warning | |||
| -- Switch ignition OFF-- Set multimeter (Fluke 83 or equivalent) to measure resistance (Ω)-- Connect multimeter between sockets 4 and 10 of VAG 1598 test box | -- Fill brake fluid reservoir to maximum level |
|
-- Remove connector from brake fluid level warning switch-- Repeat test If specified reading still not obtained: -- Check wiring for short circuit to Ground (GND) according to wiring diagram, repair as necessary If specified reading obtained after repeating test: -- Bridge connector of disconnected switch
|
| Test measurement at green 26-point instrument cluster connector | Additional steps | Specified reading | Action if specified reading not obtained |
|---|---|---|---|
| -- Connect adapter: VAG1598/4 cable to green 26-point instrument cluster connector | |||
| Voltage supply | |||
| -- Set multimeter (Fluke 83 or equivalent) to volt range-- Connect multimeter red test lead to socket 7 and black test lead to socket 11 of VAG 1598 test box | -- Switch ignition ON |
|
-- Check for open circuit in wiring according to wiring diagram, repair as necessary |
| Brake pad wear indicator | |||
| -- Switch ignition OFF-- Set multimeter to measure resistance (Ω)-- Connect multimeter between sockets 6 and 11 of VAG 1598 test box |
|
-- Replace worn brake pads and/or-- Check wiring for open circuit according to wiring diagram, repair as necessary |
| Test measurement at green 26-point instrument cluster connector | Additional steps | Specified reading | Action if specified reading not obtained |
|---|---|---|---|
| -- Connect adapter: VAG1598/4 cable to green 26-point instrument cluster connector | |||
| Engine Coolant Temperature (ECT) warning/Engine Coolant Level (ECL) warning indicator | |||
| -- Switch ignition OFF-- Set multimeter (Fluke 83 or equivalent) to measure resistance (Ω)-- Connect multimeter between sockets 3 and 11 of VAG 1598 test box | -- Fill engine coolant reservoir to maximum level |
|
-- Remove connector from Engine Coolant Level (ECL) warning switch-- Repeat test If specified reading is obtained: -- Replace ECL warning switch If specified reading is still not obtained: -- Remove connector from electronic thermal switch-- Repeat test If specified reading is obtained: -- Replace electronic thermal switch If specified reading still not obtained: -- Check wiring for short to Ground (GND) according to wiring diagram, repair as necessary |
| Test measurement at green 26-point instrument cluster connector | Additional steps | Specified reading | Action if specified reading not obtained |
|---|---|---|---|
| -- Connect adapter: VAG1598/4 cable to green 26-point instrument cluster connector | |||
| Engine Speed (RPM) signal | |||
| -- Connect engine tester VW 1367 to power and Ground (GND) in engine compartment-- Connect green wire from tester to socket 12 of VAG 1598 test box | -- Switch ignition ON and start engine |
|
-- Check wiring for open circuit according to wiring diagram, repair as necessary |
| Test measurement at green 26-point instrument cluster connector | Additional steps | Specified reading | Action if specified reading not obtained |
|---|---|---|---|
| Connect adapter: VAG1598/4 cable to green 26-point instrument cluster connector | |||
| 0.3 bar oil pressure switch | |||
| -- Switch ignition OFF-- Set multimeter (Fluke 83 or equivalent) to measure resistance (Ω)-- Connect multimeter between sockets 5 and 11 of VAG 1598 test box |
|
-- Remove connector from 0.3 bar oil pressure switch and connect to Ground (GND)-- Repeat test
|
|
| -- Start engine and let idle |
|
-- Remove connector from 0.3 bar oil pressure switch-- Repeat test
|
| Test measurement at black 14-point instrument cluster connector | Additional steps | Specified reading | Action if specified reading not obtained |
|---|---|---|---|
| -- Connect adapter cable: VAG1598/13 (if available) or : VAG1598/20 test adapter to black 14-point instrument cluster connector | |||
| Windshield washer fluid low level warning switch (for windshield and Headlamp washers) | |||
| -- Switch ignition OFF-- Set multimeter (Fluke 83 or equivalent) to measure resistance (Ω)-- Connect multimeter between socket 21 of VAG 1598 test box and Ground (GND) or between terminal 11 of : VAG1598/20 test adapter and GND | -- Fill-up washer fluid reservoir |
|
If specified reading not obtained: -- Disconnect washer pump connector-- Repeat test If specified reading obtained: -- Replace windshield washer pump If specified reading still not obtained: -- Check wiring for short to GND according to wiring diagram, repair as necessary |
| Test measurement at black 14-point instrument cluster connector | Additional steps | Specified reading | Action if specified reading not obtained |
|---|---|---|---|
| -- Connect adapter cable: VAG1598/13 (if available) or : VAG1598/20 test adapter to black 14-point instrument cluster connector | |||
| Oil pressure switch (2.5 bar) | |||
| -- Switch ignition OFF-- Set multimeter (Fluke 83 or equivalent) to measure resistance (Ω)-- Connect multimeter between socket 22 of VAG 1598 test box and Ground (GND) or between terminal 12 of test adaptor VAG 1954/20 and (GND) |
|
If specified reading not obtained: -- Remove connector from oil pressure switch (2.5 bar)-- Repeat test
|
| Test measurement at black 14-point instrument cluster connector | Additional steps | Specified reading | Action if specified reading not obtained |
|---|---|---|---|
| -- Connect adapter cable: VAG1598/13 (if available) or : VAG1598/20 test adapter to black 14-point instrument cluster connector | |||
| Oil pressure switch (2.5 bar) (cont'd.) | |||
| -- Start engine and run above 2800 RPM |
|
If specified reading not obtained: -- Remove connector from oil pressure switch (2.5 bar) and connect to GND-- Repeat test
|
| Test measurement at black 14-point instrument cluster connector | Additional steps | Specified reading | Action if specified reading not obtained |
|---|---|---|---|
| -- Connect adapter cable: VAG1598/13 (if available) or : VAG1598/20 test adapter to black 14-point instrument cluster connector | |||
| Front bulb control module | |||
| -- Set multimeter (Fluke 83 or equivalent) to volt range-- Connect multimeter between socket 11 of VAG 1598 test box and Ground (GND) or between terminal 1 of : VAG1598/20 test adapter and (GND) | -- Switch ignition ON-- Switch low beam Headlamps ON |
|
If voltage is greater than 3.5 V: -- Replace faulty bulb or bulb control module and/or-- Check wiring for open circuit according to wiring diagram, repair as necessary |
| Rear bulb control module | |||
| -- Set multimeter to volt range-- Connect multimeter between socket 12 of VAG 1598 test box and (GND) or between terminal 2 of : VAG1598/20 test adapter and (GND) | -- Switch ignition ON-- Operate brake pedal |
|
If voltage is greater than 3.5 V: -- Replace faulty bulb or bulb control module and/or-- Check wiring for open circuit according to wiring diagram, repair as necessary |