Checking the Power Supply and Ground Terminals for the Control Module

Checking the power supply and ground terminals

Checking the ground terminals








- Ignition off.
- Control module disconnected.
- Turn of all equipment in the car that takes power from the battery (the interior lighting and radio etc).
Connect an ohmmeter between the battery negative terminal and:
#53 (#A53) and #54 (#A54) on the breakout box

Other information:
- To connect the breakout box, see Connecting the breakout box, B5234T9, B5244T7 Connecting The Breakout Box.









The ohmmeter should read approximately 0 ohms for both readings.

OK - Checking the control module power supply

Not OK - Checking for an open-circuit, contact resistance and oxidation

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Checking for an open-circuit, contact resistance and oxidation
Check ground terminal 31/96 and the cables between the ground terminals and control module #A53 (#A53) and #54 (#A54) for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault and contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Check the ground lead between the battery and the bodywork for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault and contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.









Select Continue when the fault has been remedied.

Continue - Verification

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Checking the control module power supply








- Ignition off.
- Control module disconnected.
- Ignition on.
Connect a voltmeter between #35 (#A35) and #53 (#A53) on the breakout box.









The voltmeter should read battery voltage

Not OK - Checking the fuse and relay

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Checking the fuse and relay
Check that fuse 2 the fusebox in the passenger compartment is intact.
If the fuse is blown, check the cable between control module #35 (#A35) and fuse 2 for a short-circuit to ground according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.









Is the fuse intact?

Yes - Checking the voltage before the fuse

No - Verification

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Checking the voltage before the fuse




- Ignition on
Connect a voltmeter between the fuse and the right socket on the fuse holder for fuse 2 and ground.
If the voltage is approximately 12 V, check the cable between the fuse and control module #35 (#A35) for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.









Select Continue when the fault has been remedied.

Continue - Verification

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Verification




Verification

Hint: After carrying out the repair, check that the fault has been remedied.








- Ignition off.
- Turn of all equipment in the car that takes power from the battery (the interior lighting and radio etc).
- Control module disconnected.
Connect an ohmmeter between the battery negative terminal and terminal #A53 (#A53) on the breakout box.









The ohmmeter should read approximately 0 ohms.

OK - Verification, continued

Not OK - VERIFICATION FAILED

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Verification, continued








- Ignition off.
- Turn of all equipment in the car that takes power from the battery (the interior lighting and radio etc).
- Control module disconnected.
Connect a voltmeter between terminals #A35 (#A35) and #A53 (#A53) on the breakout box. The voltmeter should read battery voltage.









Were the ground terminal and power supply OK?

Yes - VERIFIED

No - VERIFICATION FAILED

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VERIFIED - FAULT FOUND

VERIFICATION FAILED - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
The fault should be diagnosed and remedied. Since this is not the case the fault-tracing process has failed.
Complete the fault-tracing for those fault or try again.

Do you want to terminate fault-tracing at this time?

Yes - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking the ground terminals

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