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Upper Electronic Module (Uem) Diagnostic Trouble Codes: Diagnosis Volvo XC90 I

Body Electrical 11 illustrations ~3722 words

DIAGNOSTIC TROUBLE CODE INFORMATION UEM-0081

Condition

Scheme 658

Scheme 658: DIAGNOSTIC TROUBLE CODE INFORMATION UEM-0081
Scheme 658: DIAGNOSTIC TROUBLE CODE INFORMATION UEM-0081

The upper electronic module (UEM) regularly compares a communication test with the rain sensor.

The diagnostic trouble code (DTC) is generated if the upper electronic module (UEM) registers that the signal cable of the rain sensor is short-circuited to ground.

The diagnostic trouble code can be diagnosed when the ignition is on.

Substitute Value

  1. Intermittent windshield wiping.
  2. High speed windshield wiping.

Possible Source

  1. The rain sensor's signal cable is short-circuited to ground.
  2. Faulty rain sensor.

Fault symptom[s]

  1. No rain sensor function.

Scheme 659

Scheme 659: CHECKING THE FUNCTION
Scheme 659: CHECKING THE FUNCTION
  1. Ignition on
  2. Activate the rain sensor. HINT: The wiper blades make a reference stroke to determine the cleanliness and condition of the windshield when the rain sensor is activated. The rain sensor is deactivated when the ignition is switched off. To reactivate the rain sensor with the ignition on, move the stalk to position "0" and then to intermittent wiping. Spray water on the windshield where the rain sensor is positioned. The wiper blades must now wipe the windshield clean. HINT: In cars equipped with the rain sensor it replaces the intermittent function. One way of checking the function of the rain sensor is to twist the collar on the lever. This changes the sensitivity of the rain sensor. The windshield wiper should make one stroke. If the intermittent or high speed functions are activated it indicates that the rain sensor function is missing.
  1. Continue Refer to «CHECKING THE WIRING»(ref-476811-S29318936452012060500000)

Scheme 660

Scheme 660: CHECKING THE WIRING
Scheme 660: CHECKING THE WIRING

Scheme 661

Scheme 661
Scheme 661

Scheme 662

Scheme 662
Scheme 662

Scheme 663

Scheme 663
Scheme 663
  1. HINT: The wiring between the upper electronic module (UEM) and the rain sensor consists of two cables.
  2. Windshield wiper stalk in position "0". Check the cable between upper electronic module (UEM) terminal #13 (#A13) and rain sensor terminal #1. Check for a short-circuit to ground. HINT: The upper electronic module (UEM) terminal #20 (#A20) is signal ground. Remedy as necessary. Other information: see «UPPER ELECTRONIC MODULE (UEM)/REARVIEW MIRROR, REPLACING»(ref-476710-S40827795872012060500000) see «RAIN SENSOR»(ref-476806-S25264844722012060500000) see «SIGNAL DESCRIPTION, UPPER ELECTRONIC MODULE (UEM)»(/volvo/xc90/i-2002-2006/remont/body-electrical/#control-module-signal-specifications) see «CONNECTING THE BREAKOUT BOX»(ref-476703-S09671458082012060500000) see «CONTENTS»(/volvo/xc90/i-2002-2006/remont/body-electrical/#wiring-and-terminals-general-diagnostics-and-tests__contents).
  1. Continue Refer to «VERIFICATION»(ref-476811-S08119925712012060500000)

DIAGNOSTIC TROUBLE CODE INFORMATION UEM-0082

Condition

The upper electronic module (UEM) regularly compares a communication test with the rain sensor.

The diagnostic trouble code (DTC) is generated if the upper electronic module (UEM) registers that the signal cable of the rain sensor is short-circuited to supply voltage. The diagnostic trouble code (DTC) is not generated if UEM-0081 is stored.

The diagnostic trouble code can be diagnosed when the ignition is on.

Substitute Value

  1. Intermittent windshield wiping.
  2. High speed windshield wiping.

Possible Source

  1. Short-circuit to supply voltage in the signal cable for the rain sensor
  2. Faulty rain sensor.

Fault symptom[s]

  1. No rain sensor function.

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-0083

Condition

The rain sensor checks itself at start.

The rain sensor checks factors such as reflections on the windshield.

The diagnostic trouble code (DTC) is stored if the rain sensor registers incorrect function.

The diagnostic trouble code (DTC) can be diagnosed with the ignition on and with an outside temperature above + 5°C (41°F).

Note. On early model years, this diagnostic trouble code (DTC) may be stored if for example there was frost on the window when the check was run. In this case, it does not help to replace any components. Fault-trace the function of the rain sensor before replacing any components.

Substitute Value

  1. Intermittent windshield wipers
  2. The windshield wipers operate at high speed.

Possible Source

  1. Frost on the windshield during the check
  2. Crack in the windshield by the rain sensor
  3. Stone chip on the windshield close to the rain sensor
  4. The rain sensor is not properly secured to the windshield
  5. Defective rain sensor.

Fault symptom[s]

  1. No rain sensor function.

DIAGNOSTIC TROUBLE CODE INFORMATION UEM-0084

Condition

The upper electronic module (UEM) regularly checks communication with the rain sensor.

The diagnostic trouble code (DTC) is generated if the upper electronic module or the rain sensor registers a fault in communication.

The diagnostic trouble code can be diagnosed when the ignition is on.

Substitute Value

  1. Intermittent windshield wiping.
  2. High speed windshield wiping.

Possible Source

  1. Contact resistance or oxidation on the signal cable.
  2. Communication disrupted.
  3. Faulty rain sensor.

Fault symptom[s]

  1. No rain sensor function.

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-0090

Condition

Scheme 664

Scheme 664: DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-0090
Scheme 664: DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-0090

The upper electronic module (UEM) checks the power supply to the LED for the PAD lamp (Passenger Airbag Deactivated). The LED is integrated in the rear view mirror.

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) registers that the power supply signal to the PAD lamp is too low.

The diagnostic trouble code (DTC) can be diagnosed when the LEDs in the rear view mirror are supplied with power, i. e. when the LEDs in the display satisfy conditions for lighting.

Substitute Value

  1. None.

Possible Source

  1. Defective upper electronic module (UEM) (internal fault).

Fault symptom[s]

  1. The SRS indicator lamp is lit.
  2. Message in the display.

Scheme 665

Scheme 665: CHECKING THE PAD-LIGHT
Scheme 665: CHECKING THE PAD-LIGHT

Scheme 666

Scheme 666
Scheme 666

Scheme 667

Scheme 667
Scheme 667
  1. Ignition off. Read off using the VCT2000 (or appropriate scan tool). Turn the ignition key to position I. Check that the requested status from the Supplemental restraint system module (SRS) is ON and that the status of the PAD lamp in the Upper electronic module (UEM) is ON when the lamp is lit. Also check if the Passenger airbag warning lamp (PAD) comes on after the ignition is switched on. If the requested status from the Supplemental restraint system module (SRS) is ON, the Upper electronic module (UEM) has activated the lamp (status is ON) but the lamp does not come on, the lamp is probably broken. Replace the upper electronic module (UEM). Check that new hardware has the correct P/N. If the requested status from the Supplemental restraint system module (SRS) is ON, but the Upper electronic module (UEM) has not activated the lamp (status is OFF), check DTCs for errors in CAN communication in the Central electronic module (CEM). Also check the CAN cables between the Upper electronic module (UEM) and the Supplemental restraint system module (SRS). Remedy as necessary. Other information see «CHECKING WIRING AND TERMINALS»(/volvo/xc90/i-2002-2006/remont/body-electrical/#wiring-and-terminals-general-diagnostics-and-tests)

Is the function OK?

  1. YES FAULT NOT FOUND: Troubleshooting has been completed.
  2. NO Refer to «REPLACING CONTROL MODULE AND PROGRAMMING»(ref-476811-S19202157832012060500000)

Condition

The upper electronic module (UEM) checks the power supply to the LEDs in the display in the rear view mirror. The five LEDs are supplied with power via the same cable and are internally mounted in the rear view mirror.

Diagnostic trouble code (DTC) UEM-0090 is stored in the control module if the upper electronic module (UEM) registers too low a signal for the power supply to the LEDs in the display in the rear view mirror.

Diagnostic trouble code (DTC) UEM-0090 can be diagnosed when the LEDs in the rear view mirror are supplied with power, i. e. when the LEDs in the display satisfy conditions for lighting.

Substitute Value

  1. None.

Possible Source

  1. The power supply cable to LEDs in the display in the rear view mirror is short-circuited to ground.

Fault symptom[s]

  1. The SRS indicator lamp is lit.

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-0091

Condition

The upper electronic module (UEM) checks the power supply to the LED for the PAD lamp (Passenger Airbag Deactivated) in the rear view mirror. The LED is integrated in the rear view mirror.

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) registers that the power supply signal to the PAD lamp is too high.

The diagnostic trouble code (DTC) can be diagnosed when the LEDs in the rear view mirror are not supplied with power, i. e. when the LEDs in the display do not satisfy conditions for lighting.

Substitute Value

  1. None.

Possible Source

  1. Defective upper electronic module (UEM) (internal fault).

Fault symptom[s]

  1. The SRS indicator lamp is lit.
  2. Message in the display.

Condition

The upper electronic module (UEM) checks the power supply to the LEDs in the display in the rear view mirror. The five LEDs are supplied with power via the same cable and are internally mounted in the rear view mirror.

Diagnostic trouble code (DTC) UEM-0091 is stored in the control module if the upper electronic module (UEM) registers too high a signal for the power supply to the LEDs in the display in the rear view mirror.

Diagnostic trouble code (DTC) UEM-0091 can be diagnosed when the LEDs in the rear view mirror are not supplied with power, i. e. when the LEDs in the display do not satisfy conditions for lighting.

Substitute Value

  1. None.

Possible Source

  1. The power supply cable to LEDs in the display in the rear view mirror is short-circuited to supply voltage.

Fault symptom[s]

  1. The SRS indicator lamp is lit.

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-0092

Condition

The display in the rear view mirror can indicate signals for two different functions, seat belt reminder or AOS. The different functions require different hardware. The upper electronic module (UEM) checks the hardware identity number on the installed rear view mirror and compares this with the software installed in the control module.

Diagnostic trouble code (DTC) UEM-0092 is stored in the control module if the upper electronic module (UEM) registers an identity number which is not compatible with the installed function.

Diagnostic trouble code (DTC) UEM-0092 can be diagnosed in ignition position II.

Substitute Value

  1. None.

Possible Source

  1. Read off identity number not compatible with installed function.

Fault symptom[s]

  1. The SRS indicator lamp is lit.

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-0093

Condition

The upper electronic module (UEM) receives information via the controller area network (CAN) indicating whether the seat belt reminder lamp should be on or off. The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) is notified that there is a short-circuit to ground or open-circuit in the power supply for the seat belt reminder lamp when it should be lit.

The diagnostic trouble code (DTC) can be diagnosed when the ignition is switched on.

Substitute Value

  1. None.

Possible Source

  1. Defective upper electronic module (UEM) (internal fault).

Fault symptom[s]

  1. The seat belt lamp does not light.

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-0094

Condition

The upper electronic module (UEM) receives information via the controller area network (CAN) indicating whether the seat belt reminder lamp should be on or off. The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) receives an indication that the seat belt reminder lamp should not be lit but the lamp is lit anyway.

The diagnostic trouble code (DTC) can be diagnosed when the ignition is switched on.

Substitute Value

  1. None.

Possible Source

  1. Defective upper electronic module (UEM) (internal fault).

Fault symptom[s]

  1. The seat belt reminder lamp is constantly on.
  2. The seat belt reminder lamp shines weakly

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A0

Condition

Scheme 668

Scheme 668: DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A0
Scheme 668: DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A0

The upper electronic module (UEM) receives information transmitted by the tire pressure sensors in the wheels, irrespective of the car. The sensors which are registered in the vehicle can be checked by running a statistical selection. A list can then be stored internally in the upper electronic module (UEM).

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) registers that the signal from the first of the four accepted sensors disappears whilst the vehicle is being driven.

The diagnostic trouble code (DTC) can be diagnosed after 10 minutes when the tire pressure warning system is active (vehicle speed is above 40 km/h (25 mph)).

Substitute Value

  1. None.

Possible Source

  1. Defective tire pressure sensor
  2. The receiver is not functioning.

Fault symptom[s]

  1. Message in the display.
  2. Warning lights and chimes/Tire pressure monitoring indication/no indication

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A1

Condition

The upper electronic module (UEM) receives information transmitted by the tire pressure sensors in the wheels, irrespective of the car. The sensors which are registered in the vehicle can be checked by running a statistical selection. A list can then be stored internally in the upper electronic module (UEM).

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) registers that the signal from the second of the four accepted sensors disappears whilst the vehicle is being driven.

The diagnostic trouble code (DTC) can be diagnosed after 10 minutes when the tire pressure warning system is active (vehicle speed is above 40 km/h (25 mph)).

Substitute Value

  1. None.

Possible Source

  1. Defective tire pressure sensor
  2. The receiver is not functioning.

Fault symptom[s]

  1. Message in the display.
  2. Warning lights and chimes/Tire pressure monitoring indication/no indication

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A2

Condition

The upper electronic module (UEM) receives information transmitted by the tire pressure sensors in the wheels, irrespective of the car. The sensors which are registered in the vehicle can be checked by running a statistical selection. A list can then be stored internally in the upper electronic module (UEM).

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) registers that the signal from the third of the four accepted sensors disappears whilst the vehicle is being driven.

The diagnostic trouble code (DTC) can be diagnosed after 10 minutes when the tire pressure warning system is active (vehicle speed is above 40 km/h (25 mph)).

Substitute Value

  1. None.

Possible Source

  1. Defective tire pressure sensor
  2. The receiver is not functioning.

Fault symptom[s]

  1. Message in the display.
  2. Warning lights and chimes/Tire pressure monitoring indication/no indication

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A3

Condition

The upper electronic module (UEM) receives information transmitted by the tire pressure sensors in the wheels, irrespective of the car. The sensors which are registered in the vehicle can be checked by running a statistical selection. A list can then be stored internally in the upper electronic module (UEM).

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) registers that the signal from the fourth of the four accepted sensors disappears whilst the vehicle is being driven.

The diagnostic trouble code (DTC) can be diagnosed after 10 minutes when the tire pressure warning system is active (vehicle speed is above 40 km/h (25 mph)).

Substitute Value

  1. None.

Possible Source

  1. Defective tire pressure sensor
  2. The receiver is not functioning.

Fault symptom[s]

  1. Message in the display.
  2. Warning lights and chimes/Tire pressure monitoring indication/no indication

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A4

Condition

The upper electronic module (UEM) receives information transmitted by the tire pressure sensors in the wheels, irrespective of the car. The sensors which are registered in the vehicle can be checked by running a statistical selection. A list can then be stored internally in the upper electronic module (UEM). The messages transmitted by the sensors contain information such as the voltage of the internal battery in the sensor.

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) receives a message from the first of the four accepted sensors indicating low battery voltage.

The diagnostic trouble code (DTC) can be diagnosed after 10 minutes when the tire pressure warning system is active (vehicle speed is above 40 km/h (25 mph)).

Substitute Value

  1. None.

Possible Source

  1. Low battery voltage in the tire pressure sensor.

Fault symptom[s]

  1. Message in the display.
  2. Warning lights and chimes/Tire pressure monitoring indication/no indication

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A5

Condition

The upper electronic module (UEM) receives information transmitted by the tire pressure sensors in the wheels, irrespective of the car. The sensors which are registered in the vehicle can be checked by running a statistical selection. A list can then be stored internally in the upper electronic module (UEM). The messages transmitted by the sensors contain information such as the voltage of the internal battery in the sensor.

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) receives a message from the second of the four accepted sensors indicating low battery voltage.

The diagnostic trouble code (DTC) can be diagnosed after 10 minutes when the tire pressure warning system is active (vehicle speed is above 40 km/h (25 mph)).

Substitute Value

  1. None.

Possible Source

  1. Low battery voltage in the tire pressure sensor.

Fault symptom[s]

  1. Message in the display.
  2. Warning lights and chimes/Tire pressure monitoring indication/no indication

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A6

Condition

The upper electronic module (UEM) receives information transmitted by the tire pressure sensors in the wheels, irrespective of the car. The sensors which are registered in the vehicle can be checked by running a statistical selection. A list can then be stored internally in the upper electronic module (UEM). The messages transmitted by the sensors contain information such as the voltage of the internal battery in the sensor.

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) receives a message from the third of the four accepted sensors indicating low battery voltage.

The diagnostic trouble code (DTC) can be diagnosed after 10 minutes when the tire pressure warning system is active (vehicle speed is above 40 km/h (25 mph)).

Substitute Value

  1. None.

Possible Source

  1. Low battery voltage in the tire pressure sensor.

Fault symptom[s]

  1. Message in the display.
  2. Warning lights and chimes/Tire pressure monitoring indication/no indication

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A7

Condition

The upper electronic module (UEM) receives information transmitted by the tire pressure sensors in the wheels, irrespective of the car. The sensors which are registered in the vehicle can be checked by running a statistical selection. A list can then be stored internally in the upper electronic module (UEM). The messages transmitted by the sensors contain information such as the voltage of the internal battery in the sensor.

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) receives a message from the fourth of the four accepted sensors indicating low battery voltage.

The diagnostic trouble code (DTC) can be diagnosed after 10 minutes when the tire pressure warning system is active (vehicle speed is above 40 km/h (25 mph)).

Substitute Value

  1. None.

Possible Source

  1. Low battery voltage in the tire pressure sensor.

Fault symptom[s]

  1. Message in the display.
  2. Warning lights and chimes/Tire pressure monitoring indication/no indication

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A8

Condition

The upper electronic module (UEM) receives information transmitted by the tire pressure sensors in the wheels, irrespective of the car. The sensors which are registered in the vehicle can be checked by running a statistical selection. A list can then be stored internally in the upper electronic module (UEM).

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) registers that the signal from fewer than four of the accepted sensors has been received during an operating cycle.

The diagnostic trouble code (DTC) can be diagnosed after 10 minutes when the tire pressure warning system is active (vehicle speed is above 40 km/h (25 mph)).

Substitute Value

  1. None.

Possible Source

  1. A rim without a tire pressure sensor has been installed
  2. A rim with a tire pressure sensor not intended for this model has been installed (the sensor is unable to communicate with the receiver)
  3. Defective tire pressure sensor
  4. The receiver is not functioning.

Fault symptom[s]

  1. Message in the display.
  2. Warning lights and chimes/Tire pressure monitoring indication/no indication

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-00A9

Condition

The upper electronic module (UEM) has a configuration file which controls certain internal settings. The upper electronic module (UEM) checks that the configuration file is correct.

The diagnostic trouble code (DTC) is stored if the upper electronic module (UEM) registers that the configuration file is incorrect or missing.

The diagnostic trouble code (DTC) can be detected when the control module is initialized after being reset or when diagnostic trouble codes (DTCs) are erased.

Substitute Value

  1. Factory settings are used.

Possible Source

  1. Incorrect or missing configuration file.

Fault symptom[s]

  1. None.

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-E001

Condition

The control modules transmit and receive information via a standardized serial communication method - CAN (Controller Area Network). The diagnostic trouble code (DTC) is stored if the control module registers serious interference (CAN communication blocked).

Note. In the event of system communication problems, it is not possible to communicate with the control module. Therefore it will only be possible to read off the fault if it is intermittent.

Substitute Value

  1. The control module shuts itself off ("bus-off"). HINT: The control module will remain shut off until the power supply is broken (15, 30, X). When the power supply is connected the control module will make a new attempt to communicate.

Possible Source

  1. Short-circuit between the control area network (CAN) wiring
  2. Open-circuit in the control area network (CAN) wiring
  3. Internal fault in the control module
  4. Internal fault in another control module in the same part of the control area network (CAN).

Fault symptom[s]

  1. Cannot be controlled with the remote control
  2. The interior lighting does not operate
  3. The power sun roof does not operate
  4. The alarm does not function at all
  5. No rain sensor function.

see DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-E001

DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-E003

Condition

The control module compares its configuration ID with the signal configuration transmitted on the control area network (CAN) by the central electronic module (CEM). If the configuration IDs do not correspond the fault code is stored. The diagnostic trouble code (DTC) is also stored if the communication between the control module and the central electronic module (CEM) is interrupted.

Note. In the event of open-circuit in both the control area network (CAN) cables, it is not possible to communicate with the control module. Therefore it will only be possible to read off the diagnostic trouble code (DTC) if this type of fault is intermittent. When the diagnostic trouble code (DTC) is stored, the control module responds to the diagnostic command, however normal control area network (CAN) communication does not work. ("Expulsion mode")

Substitute Value

  1. None.

Possible Source

  1. Faulty control area network (CAN) configuration ID. (The node is not intended for this car, for example a used control module with different software/hardware.)
  2. Open-circuit in the control area network (CAN) wiring between the control module and the central electrical module (CEM).

Fault symptom[s]

  1. Cannot be controlled with the remote control
  2. The interior lighting does not operate
  3. The power sun roof does not operate
  4. The alarm does not function at all
  5. No rain sensor function.

see DIAGNOSTIC TROUBLE CODE (DTC) INFORMATION UEM-E003

READING OFF DIAGNOSTIC TROUBLE CODES (DTCS)

  1. Ignition on. Read off the diagnostic trouble code (DTC) that is stored in the car. Make a note of the code for reporting purposes.

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