SRS-212
Diagnostic Trouble Code (DTC) SRS-212 - Driver's Airbag, open-circuit or capacitance too lowSpecial tools:
- 998 8695
- Volvo Scan Tool (ST)
DTC Conditions
If resistance in the circuit is too high or capacitance too low for over 10 seconds, the diagnostic trouble code (DTC) SRS-212 is stored.
Cause of fault
Resistance too high.
- Open-circuit in the SRS ignition cable or connectors between steering wheel module and SRS sensor module.
- Open-circuit in steering wheel module (resistance too high in igniter).
- Open-circuit in contact reel.
Capacitance too low.
- Capacitance too low or open circuit in the SRS ignition cable igniter connector capacitor.
Fault symptoms
No symptoms apart from the SRS warning lamp lighting.
WARNING: There is a risk that the SRS steering wheel module will not work if this diagnostic trouble code (DTC) is posted.
Action
The fault can be found by a process of elimination.
WARNING: Under no circumstances use an ohmmeter or other live measuring instrument to take readings on a disconnected non-deployed steering wheel module. This could deploy the airbag.
NOTE: Follow the operations in the chapter carefully and carry out operations in the correct order.
Checking Diagnostic Trouble Code (DTC) And Type Of Fault
Before starting to remove components, the Volvo Scan Tool (ST) should be used to check whether the fault is permanent or intermittent.
- Connect the Volvo Scan Tool (ST. Displaying & Reading Trouble Codes
- Read off diagnostic trouble code (DTC).
- Clear diagnostic trouble code (DTC).
- It should not be possible to clear diagnostic trouble code (DTC) SRS-212 if the fault is permanent.
If diagnostic trouble code (DTC) SRS-21 2 could not be cleared (the fault persists):
The fault is permanent.
- Continue with Removing steering wheel module, see below.
If diagnostic trouble code (DTC) SRS-212 could be cleared:
The fault is not permanent. The fault could be intermittent.
Attempt to provoke the intermittent fault at every step of the fault tracing process by shaking connectors and cabling and turning the steering wheel while taking readings.
NOTE: If no fault has been isolated by the end of the fault tracing process start by replacing the contact reel.
- Continue with Removing steering wheel module.
Removing Steering Wheel Module
- Make a note at radio code it anti-theft coded radio in. stalled.
- Ignition off.
- Disconnect battery negative lead.
- Remove Steering wheel module.
WARNING: Under no circumstances use an ohmmeter or other live measuring instrument to take readings on a disconnected non-deployed steering wheel module. This could deploy the airbag.
NOTE: Put the steering wheel module with its metal side (back) down in a protected place (in the cargo compartment tar example).
Checking Diagnostic Trouble Codes (DTC) With Steering Wheel Module Replaced By Special Tool 998 8695
- Connect special tool 9988695 to SRS ignition cable igniter connector.
NOTE: The special tool should be checked and defect-free. If the tool is defective it will cause errors in the diagnosis and make fault tracing harder. If in doubt check the special tool in accordance with BC.
- Switch ignition to position II.
- Connect battery negative lead.
- Read off diagnostic trouble code (DTC).
- Clear diagnostic trouble code (DTC).
It should be possible to clear diagnostic trouble code (DTC) SRS-212 if the fault is in the steering wheel module.
If diagnostic trouble code (DTC) SRS-212 could be cleared:
No fault detected by the SRS on-board diagnostic (OBD) system with the steering wheel module removed and replaced by special tool 9988695.
The fault is probably in the steering wheel module. One last check should be made before replacing the steering wheel module.
- Continue with Installing steering wheel module.
If diagnostic trouble code (DTC) SRS-21 2 could not be cleared (the fault persists):
The fault persists even with the steering wheel module removed. This means that the steering wheel module is OK.
The fault is probably in the contact reel or SRS ignition cable.
- Continue with Removing steering wheel covers.
Installing Steering Wheel Module
- ignition off.
- Disconnect battery negative lead.
- Remove special tool 9988695.
- Connect connector to steering wheel module.
- Install steering wheel module.
WARNING: Under no circumstances use an ohmmeter or other live measuring instrument to take readings on a disconnected non-deployed steering wheel module. This could deploy the airbag.
Checking Diagnostic Trouble Code (DTC) With The Steering Wheel Module Installed
- Switch ignition to position II.
- Connect battery negative lead.
- Read off diagnostic trouble code (DTC).
If the fault is in the steering wheel module diagnostic trouble code (DTC) SRS-212 should be stored.
If diagnostic trouble code (DTC) SRS-212 is present:
There is an open-circuit in the steering wheel module.
^ Replace steering wheel module.
If no diagnostic trouble code (DTC) is present:
The SRS on-board diagnostic (OBD) system has not detected a fault with the steering wheel module installed.
The fault is intermittent in the contact reel or SRS ignition cable.
Removing Steering Wheel Module
- Ignition off.
- Disconnect battery negative lead.
- Remove steering wheel module.
WARNING: Under no circumstances use an ohmmeter or other live measuring instrument to take readings on a disconnected non-deployed steering wheel module. This could deploy the airbag
NOTE: Put the steering wheel module with its metal side (back) down in a protected place (in the cargo compartment for example).
- Install special tool 9988695.
Removing Steering Wheel Covers
- Ignition off.
Remove:
- screws in countersunk outer holes (2 x Torx 15) from beneath cover.
- screws in inner holes (2 x Torx 25) from beneath cover.
- ignition key.
- upper and lower cover from the steering column.
Checking contact reel connector
- Ignition off.
- Disconnect contact reel connector.
- Check cable terminals in the female and male halves of the connector.
Cable terminals must not be damaged or pressed back.
- Connect connector to contact reel. Check that male and female connector halves lock into each other.
If the female and male connector halves are OK:
- Continue with CF9.
If the male connector half is defective:
^ Replace contact reel.
If the female connector half is defective:
^ Replace SRS cable harness.
Checking Diagnostic Trouble Codes (DTC) With The Contact Reel Connector Connected
- Switch ignition to position II.
- Connect battery negative lead.
- Read off diagnostic trouble code (DTC).
- Clear diagnostic trouble code (DTC).
It should not be possible to clear diagnostic trouble code (DTC) SRS-212 if the fault persists.
If diagnostic trouble code (DTC) SRS-212 could not be cleared:
The fault still exists.
- Continue with CF1O.
If diagnostic trouble code (DTC) SRS-212 could be cleared:
The SRS on-board diagnostic (OBD) system has not detected a fault with the SRS ignition cable contact reel connector installed.
The fault is intermittent in the contact reel.
^ Replace contact reel.
Checking Resistance In Contact Reel
- Ignition off.
- Disconnect battery negative lead.
- Remove special tool 9988695.
- Disconnect contact reel connector.
- Connect an ohmmeter between terminal 1 on the contact reel half of the connector (section A in the figure above) and terminal 1 on the igniter connector (left connecting pin, closest to service hole"). See connection in Figure.
The ohmmeter should read approx. 0 Ohms.
NOTE: If the ohmmeter test pins are too big to fit into the connector terminal holes, insert a thin metal rod (or a piece of stripped cable) with a maximum diameter of 1 mm, and take readings from that. Take care not to damage the connector cable terminals.
- Connect an ohmmeter between terminal 2 on the contact reel half of the connector and the "service hole" on the igniter connector. See connection in Figure.
The ohmmeter should read approx. 0 Ohms.
Even if the ohmmeter reading is OK there may be an intermittent fault in the contact reel.
- Repeat resistance measurements while slowly turning the steering wheel to full lock in both directions.
The ohmmeter should read approx. 0 Ohms.
If both readings are OK:
There is an open-circuit in the SRS ignition cable between the connector and the sensor module or there is a fault in the capacitor in the SRS ignition cable igniter connector.
- Continue with Checking capacitor in the igniter connector.
If the reading is abnormal:
If the ohmmeter reads infinity in any steering wheel position there is an open-circuit in the contact reel.
^ Replace contact reel.
Checking Capacitor In The Igniter Connector
Resistance check
NOTE: If there is a measuring instrument with a capacitance measuring facility use "Alternative capacitance check" on the next page.
An ohmmeter can be used to check the capacitor in the SRS ignition cable igniter connector.
- Ignition off.
- Connect measuring instrument terminals between the connector "service hole" and terminal 2 right connecting pin. See connection in Figure. (The capacitor will charge.)
The ohmmeter reading should increase rapidly and stop at infinity.
- Reverse the position of the ohmmeter positive and negative terminals and connect them to the connector as above. See connection in Figure. (The capacitor will discharge and charge.)
The ohmmeter reading should drop rapidly to approx. 0 Ohms and then increase to infinity.
Alternative Capacitance Check
A measuring instrument with a capacitance measuring facility can be used to check the capacitor in the SRS ignition cable igniter connector.
- Ignition off.
- Connect measuring instrument terminals between the connector service hole and terminal 2 right connecting pin. See connection in Figure.
The measuring instrument should read between 0.46 microfarad and 0.46 microfarad.
If the reading is OK:
There is no open-circuit in the capacitor.
- Continue with Checking resistance in the ignition cabling and sensor module.
If the reading is abnormal:
If the ohmmeter reading is constantly high without dropping or increasing there is an open-circuit in the capacitor.
^ Replace contact reel.
Checking Resistance In The Ignition Cabling And Sensor Module
- Ignition off.
- Connect an ohmmeter between the connecting sockets in the sensor module halt of the connector (part B in the figure).
Take care not to damage connecting sockets.
The ohmmeter should read approx. 47 Kohms.
If the reading is OK:
SRS ignition cabling and sensor module are OK.
^ Replace contact reel.
If the reading is abnormal:
If the ohmmeter reads infinity there is a open-circuit in the SRS ignition cable between the connector and sensor module or an open-circuit in the sensor module.
Checking SRS sensor module connector
- Ignition off.
- Expose and remove SRS sensor module connector.
NOTE: Never touch the sensor module pins. There is a risk of static discharge which could damage the sensor module.
- Check cable terminals in the female half of the connector and the male half of the sensor module.
Cable terminals must not be damaged or pressed back.
- Install and remove connector from sensor module. Check that the connector locks into the sensor module.
If the female and male connector halves are OK:
- Continue with Checking SRS ignition cable resistance.
If the male sensor module connector half is defective:
^ Replace sensor module.
If the female connector half is defective:
^ Replace SRS cable harness
Checking SRS Ignition Cable Resistance
NOTE: Never touch the sensor module pins. There is a risk of static discharge which could damage the sensor module.
Connect an ohmmeter between SRS ignition cable connector (removed from the contact reel) and sensor module connector (removed from sensor module).
- Ignition off.
- Connect an ohmmeter between sensor module connector terminal 10 and SRS ignition cable connector terminal 1.
The ohmmeter should read approx. 0 Ohms.
NOTE: If the ohmmeter test pins are too big to fit into the sensor module connector, insert a thin metal rod (or a piece of stripped cable) with a maximum diameter of 1 mm, and take readings from that. Take care not to damage the connector cable terminals.
- Connect an ohmmeter between sensor module connector terminal 11 and SRS ignition cable connector terminal 2.
The ohmmeter should read approx. 0 Ohms.
If both readings are OK:
The SRS ignition cable is OK.
^ Replace sensor module.
If the reading is abnormal:
If the ohmmeter reads infinity in any of the readings taken, there is an open-circuit in the SRS ignition cable between the contact reel connector and the sensor module connector.
^ Replace SRS cable harness.