Vauxhall Workshop Service and Repair Manuals

No.

TECH 1 Display

Conditions for Checking

Nominal Value

Trouble Codes

Termi-nal

02

SQUIB DRIVER

Ignition ON

Turn steering wheel very slowly in both directions to full lock

Note:

The measured value indicated by TECH 1 is a replacement value; i.e. it is only used for recognition of alterations to the resistance in the squib circuit, caused, for example, by a loose contact or a defect in the contact unit.

The displayed value is usually greater than 0 % but less than 100 %. If the value is greater than 200 %, this indicates an open circuit.

The steering wheel must be turned very slowly if a loose contact is to be recognized, as the TECH 1 display is only brought up to date about once a second.

less than 100 % Value must be approximately constant; there must be no large oscillations

21, 22, 31

1, 2

Trouble-shooting:

Nominal Value:

Cause of Fault:

(If nominal value is not attained)

For checking operations, observe the safety regulations detailed in section 1.1 of these Checking Procedures.

The vehicle battery must always be disconnected except when the checking operations include voltage measurement.

·   Ignition OFF

·   Disconnect battery

·   Disconnect instrument panel/contact unit wiring harness plug X 91 (orange) (observe safety measures)

·   Do not disconnect instrument panel/contact unit wiring harness plug X 94

·   Disconnect co-driver airbag unit wiring
harness plug X 93 (if present)

·   Disconnect airbag control unit wiring harness plug X 90 (observe safety measures)

Important:

If trouble code 21 or trouble code 22 is stored, also measure the co-driver airbag unit circuit according to test step 03.

The control unit cannot determine which squib circuit has a short circuit to ground or voltage.

·   Connect battery

·   Ignition ON

·   Measure voltage:

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1 (control unit side)

     to:          ground

     and

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 2 (control unit side)

     to:          ground

less than 0.1 V

less than 0.1 V

·   Short circuit to voltage

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1

     to:          airbag control unit wiring harness plug X 90 Ter. 1

·   Short circuit to voltage

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 2

     to:          airbag control unit wiring harness plug X 90 Ter. 2

·   Ignition OFF

·   Disconnect battery

·   Using multimeter, measure resistance:

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1 (control unit side)

     to:          instrument panel/contact unit wiring harness plug X 91 Ter. 2 (control unit side)

less than 2 W

·   Lead interruption

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1

     to:          airbag control unit wiring harness plug X 90 Ter. 1

·   Lead interruption

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 2

     to:          airbag control unit wiring harness plug X 90 Ter. 2

·   Short circuit bridge in airbag control unit wiring harness plug X 90 defective (short circuit bridge between Ter. 1 and Ter. 2)

·   Insert Adapter KM-609-9 from Electronic Kit I in control unit plug, in the slot under Ter. 1 and Ter. 2, (short circuit bridge opened)

·   Using multimeter, measure resistance:

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1 (control unit side)

     to:          instrument panel/contact unit wiring harness plug X 91 Ter. 2 (control unit side)

greater than

100 kW (¥)

·   Short circuit in wiring harness

     from:      airbag control unit wiring harness plug X 90 Ter. 1

     to:          airbag control unit wiring harness plug X 90 Ter. 2

·   Short circuit bridge in airbag control unit wiring harness plug X 90 defective (short circuit bridge between Ter. 1 and Ter. 2)

·   Using multimeter, measure resistance:

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1 (control unit side)

     to:          ground

     and

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 2 (control unit side)

     to:          ground

greater than

100 kW (¥)

greater than

100 kW (¥)

·   Short circuit to ground

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1

     to:          airbag control unit wiring harness plug X 90 Ter. 1

·   Short circuit to ground

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 2

     to:          airbag control unit wiring harness plug X 90 Ter. 2

Check contact unit U 20:

·   Remove driver's airbag unit U 21 according to Service Instructions (observe safety measures)

·   Disconnect driver's airbag unit wiring harness plug X 92

·   Inspect driver's airbag unit U 21

     (do not measure at terminals of airbag unit / observe safety measures)

No damage to wiring harness plug and short circuit bridge

·   Driver's airbag unit U 21 defective

·   Connect battery

·   Ignition ON

·   Measure voltage:

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1 (contact unit side)

     to:          ground

     and

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 2 (contact unit side)

     to:          ground

less than 0.1 V

less than 0.1 V

·   Contact unit U20 defective.

·   Ignition OFF

·   Disconnect battery

·   Using multimeter, measure resistance:

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1 (contact unit side)

     to:          ground

     and

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 2 (contact unit side)

     to:          ground

greater than

100 kW (¥)

greater than

100 kW (¥)

·   Contact unit U 20 defective.

·   Turn steering wheel from straight-ahead position up to stop, once to the left and once to the right

·   Using multimeter, measure resistance:

              from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1 (contact unit side)

     to:          ground

     and

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 2 (contact unit side)

     to:          ground

greater than

100 kW (¥)

greater than

100 kW (¥)

·   Contact unit U 20 defective.

·   Using multimeter, measure resistance:

     from:      driver's airbag unit wiring harness plug X 92 Ter. 1 (cable colour GEWS: yellow/white)

     to:          driver's airbag unit wiring harness plug X 92 Ter. 2 (cable colour GE: yellow)

Note:

Use Adapter KM-609-20

Short circuit bridge in instrument panel/contact unit wiring harness plug is closed.

less than 2 W

·   Contact unit U 20 defective.

·   Turn steering wheel from straight-ahead position up to stop, once to the left and once to the right

·   Using multimeter, measure resistance:

     from:      driver's airbag unit wiring harness plug X 92 Ter. 1 (cable colour GEWS: yellow/white)

     to:          driver's airbag unit wiring harness plug X 92 Ter. 2 (cable colour GE: yellow)

Note:

Use Adapter KM-609-20

Short circuit bridge in instrument panel/contact unit wiring harness plug is closed.

less than 2 W

·   Contact unit U 20 defective.

·   Insert Adapter KM-609-15 from Electronic Kit I in instrument panel/contact unit wiring harness plug X 91, contact unit side

     (in doing so, short circuit bridge is opened)

·   Using multimeter, measure resistance:

     from:      driver's airbag unit wiring harness plug X 92 Ter. 1 (cable colour GEWS: yellow/white)

     to:          driver's airbag unit wiring harness plug X 92 Ter. 2 (cable colour GE: yellow)

Note:

Use Adapter KM-609-20

greater than

100 kW (¥)

·   Contact unit U 20 defective.

·   Turn steering wheel from straight-ahead position up to stop, once to the left and once to the right

·   Using multimeter, measure resistance:

     from:      driver's airbag unit wiring harness plug X 92 Ter. 1 (cable colour GEWS: yellow/white)

     to:          driver's airbag unit wiring harness plug X 92 Ter. 2 (cable colour GE: yellow)

Note:

Use Adapter KM-609-20

greater than

100 kW (¥)

·   Contact unit U 20 defective.

·   Connect airbag control unit wiring

     harness plug X 90

     (observe safety measures)

Note:

Driver's airbag unit only:

As neither the contact unit nor the driver's airbag unit is connected, trouble code 31 must be set.

Driver's and co-driver's airbag units only:

As neither the contact unit nor the driver's and co-driver's airbag units are connected, trouble codes 31 and 33 must be set.

·   Connect battery

·   Ignition ON

     (TECH 1 is not connected)

Fault recognized and stored after approx. 5 s (System telltale ON)

·   Control unit defective.

·   Read trouble code with TECH 1

     Only driver's airbag unit U 21:

     Only driver's airbag unit U 21

     and co-driver unit U 22:

Trouble code 31 present

Trouble codes 31 and 33 present

·   Control unit defective.

·   Control unit defective.

·   Bridge instrument panel/contact unit

     wiring harness plug X 91

     from:      instrument panel/contact unit wiring harness plug X 91 Ter. 1(control unit side)

     to:          instrument panel/contact unit wiring harness plug X 91 Ter. 2(control unit side)

Note:

Use Adapter KM-609-20

·   Read trouble code with TECH 1

     Only driver's airbag unit U 21:

     Only driver's airbag unit U 21 and co-driver unit U 22:

Trouble code 31 not present

Trouble code 31 not present

Trouble code 33 present

·   Control unit defective.

·   Control unit defective.

If  nominal values attained

·   Driver's airbag unit U 21 defective.

Note:

After diagnosis/repairs ensure that all plug connections have been properly restored.Then clear all trouble codes with TECH 1.