B1532

Symptom: ABS (ANTI LOCK) warning lamp on, no ABS function.

B1532

Fault symptom

ABS (ANTI LOCK) warning lamp on, no ABS function.

Condition

Battery voltage < about 9 V for more than 60 seconds.

Diagnostic help

A reading of the control module's power supply (+30 circuit) can be obtained with the ISAT scan tool.

-	Select ”READ VALUES”.

-	- Select ”BATTERY VOLTAGE”.

The current battery voltage will be displayed. If the +15 circuit is not connected to the control module, perhaps because fuse 19 has blown, no communication will be established.

Diagnostic procedure

1 Check the fuses

•	Check that fuse 19 is intact.

•	Check that current is supplied to fuse 19.

Connect the test lamp to fuse 19 and a good grounding point.

Fuse inspection OK?

yes

Continue with point 2.

no

Rectify the fault and if necessary continue fault diagnosis as described in Service Manual 3:2 Electrical system, +15 power supply.

2 Check the battery

-	Check the condition of the battery. See Service Manual 3:1, Electrical system, Battery.

Is the condition of the battery OK?

yes

Continue with point 2.

no

Rectify the fault.

3 Check the control module's power supply and connection to ground

-	Unplug the control module's 4-pin connector.

-	Ignition switch in ON position.

-	Take voltage readings on the control module's connector:

•

pin 1 to battery positive (B+) <0.5

•

pin 2 to battery positive (B+) <0.5

•

pin 3 to battery negative (B-) <0.1 V

Are all voltage readings OK?

yes

Continue with point 3.

no

Check the wiring, including connectors and grounding point G30. Rectify if necessary.

4 Final check

-	Clear the diagnostic trouble code.

-	Drive the car at varying engine loads and rpm for 5 minutes.

-	Read the diagnostic trouble code.

Is the diagnostic trouble code stored?

yes

Continue with

no

The diagnostic procedure carried out was correct or the fault is of an intermittent nature.