Volvo 850. Manual - part 60

4-1-8  ....................  No Control Signal To ECC Power Stage

4-1-9  .......  ECC Power Stage Emitting Faulty Diagnostic Signal

4-2-0  ................  ECC Control Module Fault, Program Memory

5-1-1  .........................  Self-Adjustment Of Damper Motor

                                  Limit Positions Not Carried Out

         TEST MODE 1

         1) Turn ignition on. Press button on diagnostic unit "A" for

about one second. Read LED flashes. If LED does not illuminate, go to

ON-BOARD DIAGNOSTIC UNIT CHECK under TESTING.

         2) If LED flashes DTC 1-1-1, no faults are stored. If LED

flashes other than DTC 1-1-1, display DTCs and perform appropriate DTC

trouble shooting. To erase code, see ERASING CODES.

         TEST MODE 2

         1) Turn ignition on. Press button on diagnostic unit "A"

twice (for about one second each time). LED should start flashing

rapidly once TEST MODE 2 is activated. If LED does not start flashing

rapidly after button is pressed, go to ON-BOARD DIAGNOSTIC UNIT CHECK

under TESTING.

         2) If LED flashes DTC 1-1-2, signal from solar sensor is

okay. If LED flashes DTC 1-1-3, signal from speedometer is okay. If

neither DTC is present, go to next step.

         3) If DTC 1-1-2 is not present, check solar sensor. Go to

SOLAR SENSOR under TESTING. If DTC 1-1-3 is not present, check speed

sensor signal. Go to SPEEDOMETER SIGNAL under TESTING. To exit TEST

MODE 2, turn ignition off.

         TEST MODE 4

         1) Turn ignition on. Press button on diagnostic unit "A" 4

times (for about one second each time). LED should illuminate. If LED

illuminates, go to next step. If LED does not illuminate, go to

ON-BOARD DIAGNOSTIC UNIT CHECK under TESTING.

         2) Control codes must be entered one step at a time. See

TEST MODE 4 CONTROL CODES table. LED should go off after each digit is

entered. Entering each digit in a code must be made within 4 seconds,

as failure to do so will abort input and TEST MODE 4 must be

restarted.

TEST MODE 4 CONTROL CODES

Code                                                    Test

1-1-1  ..............................  Controlling A/C Relay

3-1-1  ...................................  ( 1) Normal Speed

3-1-2  .......................................  ( 1) X2 Speed

3-1-3  ..................................  ( 1) (2) X10 Speed

9-9-9  .................................  Self-Adjustment Of

                                Damper Motor Limit Positions

(1) - Changes data transmission speed/rate from ECC control

      module to on-board diagnostic unit.

(2) - Used only with Volvo Diagnostic Key (998 8670).

         Controlling A/C Relay

         Enter control code 1-1-1 by pressing button on diagnostic

unit 3 times, with a short pause in between to allow LED to come on

again. ECC control module will now switch A/C relay on and off 5 times

(10 seconds on, 10 seconds off), switch A/C compressor on and off, and

turn control panel A/C indicator on and off. If A/C relay does not

respond as indicated, check A/C relay. See  A/C RELAY CHECK under

TESTING.

         Self-Adjustment Of Damper Motor Limit Positions

         1) Turn ignition on. Place fan (blower motor) lever in manual

mode. Turn function selector to AUT (automatic). Ensure system is in

TEST MODE 4.

         2) Enter control code 9-9-9 by pressing button on diagnostic

unit 9 times in quick succession. Enter each of the 9 series 3 times,

with a short pause in-between to allow LED to come on again. ECC

control module is now ready to adjust damper motor limit positions

automatically.

         3) Wait about 10 seconds for fan to start. Turn ignition off

to exit TEST MODE 4. Turn ignition on. AC OFF and REC indicator on A/C

control panel should flash. Drive car for a few minutes at speeds

greater than 20 MPH.

         4) Stop car and turn engine off, but leave ignition on for at

least 2 minutes to enable ECC control module to store all values.

Start TEST MODE 1 and record DTCs. If DTC 1-1-1 appears, self-

adjustment is complete. If DTC 5-1-1 appears, self-adjustment is not

complete.

         Changing Data Transmission Speed/Rate From ECC Control Module

         To On-Board Diagnostic Unit

         Enter desired control code (3-1-1 or 3-1-2) by pressing

button on diagnostic unit "A", with a short pause in-between to allow

LED to come on again. System always starts at normal speed unless

another option is selected. If another option was selected, system

will revert to normal speed each time ignition is turned off.

         ERASING CODES

         1) All codes must be displayed at least once before they can

be erased. To erase codes, ensure selector cable is connected to

terminal No. 1 of diagnostic unit "B". See  Fig. 2. Press and hold

diagnostic button for at least 5 seconds. LED should illuminate 3

seconds after button is released.

         2) Press and hold diagnostic button for a minimum of 5

seconds more. When button is released, LED should go out. Ensure codes

have been erased by pressing diagnostic button once. If display shows

1-1-1, codes have been erased/cleared. If a DTC will not erase/clear,

perform that particular code’s diagnosis again.

         DTC 1-2-1 OUTSIDE TEMP. SENSOR CIRCUIT SHORTED TO GROUND

         1) Turn ignition off. Install Test Unit (981 3190) and

Adapter (981 3194) between ECC control module and harness connector.

See Fig. 3. Using ohmmeter, connect test leads between ground and test

unit pins No. 6, 9, 10 and 56. Ohmmeter should read zero ohms in each

terminal. If resistance is as specified, go to next step. If

resistance is not as specified, check for open circuit.

         2) Disconnect Adapter (981 3194) from ECC control module.

Disconnect outside temperature sensor (located on right rear of engine

compartment). See Figs. 4 and 5. Connect ohmmeter leads between test

unit pins No. 10 and 14. Ohmmeter should read infinity. If reading is

as specified, go to next step. If reading is not as specified, check

for shorted circuit between sensor harness connector and ECC control

module.

         3) Connect ohmmeter leads between outside temperature sensor

terminals. Resistance should be 8000-12,000 ohms. If resistance is not

as specified, replace outside temperature sensor. Clear and recheck

for codes.

Fig. 3:  Using Test Unit To Diagnose ECC System

Courtesy of Volvo Cars of North America.

Fig. 4:  Identifying Outside Temperature Sensor Terminals

Courtesy of Volvo Cars of North America.

Fig. 5:  Locating Outside Temperature Sensor

Courtesy of Volvo Cars of North America.