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B76531.0
ELECTRONICALLY CONTROLLED HYDRAULIC SYSTEMS
Fault finding - Interpretation of XR25 bargraphs
38
ABS BOSCH
5.3
Bargraph 1, right hand side extinguished
Code present
1
None. NOTES
Fiche n° 53
Check that the XR25 kit is not the cause of the fault by trying to communicate with the computer of
another vehicle. If the XR25 kit is not at fault and it will not communicate with any other computer in the
same vehicle, it is possible that a faulty computer is corrupting fault finding lines K and L . Locate this
computer by disconnecting the lines one by one.
Check that the ISO interface is correctly in position S8 and that you are using the most recent XR25
cassette and the correct access code.
Check the battery voltage and carry out the necessary operations to obtain the correct voltage(9.4Volts<
U battery<17.4Volts)
Check the presence and condition of the ABS fuse on the connection unit of the passenger compartment
(10A).
Check the connection of the computer connector and the condition of its connection.
Check the connection and condition of the connection at the R36 dashboard / ABS connection.
Check the ABS earth wires (tighten the two earth screws above the ABS assembly).
Check that the computer is correctly fed :
-earth on track 19 of the 31 track connector,
-+ after ignition feed on track 15 of the 31track connector.
Check that the diagnostic socket is correctly fed :
-+ before ignition feed on track 16,
-earth on track 5.
Check the continuity and insulation of the lines in the diagnostic socket / ABS computer connection:
- between track 12 of the computer connector and track 15 of the diagnostic socket,
- between track 11 of the computer connector and track 7 of the diagnostic socket.
If dialogue is still not established after these tests, replace the ABS computer.,
When communication is established, deal with any fault bargraphs which may be
illuminated. AFTER REPAIR
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B76531.0
ELECTRONICALLY CONTROLLED HYDRAULIC SYSTEMS
Fault finding - Interpretation of XR25 bargraphs
38
ABS BOSCH
5.3
After replacing the computer, carry out another XR25 test.AFTER REPAIR
Bargraph 1 left hand side illuminated
Power supply/computer
1
None.
NOTES
Fiche n° 53
Erase the computer memory, exit the fault finding (G13*) and switch off the ignition.
Carry out a new XR25 test. If the "power supply / computer" fault persists, replace the ABS computer.
Check the condition and position of the 60A ABS fuse in the engine connection unit (white mounting).
Ensure continuity between this fuse and tracks 17 and 18 of the computer connector (presence of positive
before ignition feed on both tracks). Check the tightness and condition of the battery terminals.
Check the connections on the 31 track connector of the ABS computer.
Check the ABS earths (above the hydraulic assembly) and visually check all the ABS wiring.
38-5
Page 267 of 363

B76531.0
ELECTRONICALLY CONTROLLED HYDRAULIC SYSTEMS
Fault finding - Interpretation of XR25 bargraphs
38
ABS BOSCH
5.3
Erase computer memory(GO**).
Carry out a road test followed by a check with the XR25 kit.AFTER REPAIR
Bargraphs 2, 3, 4 or 5 right or left hand side flashing
Solenoid valve circuit
Even if present at time of testing, these faults will always be declared by a
flashing bargraph.
To confirm their presence and therefore the need to apply the fault finding
described below start command G20*. The fault is present if the bargraph
appears illuminated at the end of the command.
If bargraph 11 left hand side is also illuminated, deal with bargraph 11 left hand
side as a priority.
NOTES
Fiche n° 532 - 3 - 4 - 5
Check the ABS earths (tightening of the two screws above the hydraulic assembly).
Check the condition and position of the 60A ABS fuse in the engine connection unit (white mounting).
Check the connection and condition of the connections on the 31 track connector of the computer.
Erase the computer memory, exit the fault finding mode(G13*) switch off the ignition.
Switch on the ignition and carry out a new test with the XR25 kit, using command G20*.
If the fault "solenoid valve circuit"reappears, replace the ABS computer.
38-6
Page 268 of 363

B76531.0
ELECTRONICALLY CONTROLLED HYDRAULIC SYSTEMS
Fault finding - Interpretation of XR25 bargraphs
38
ABS BOSCH
5.3
Erase computer memory(GO**).
Carry out a road test followed by a check with the XR25 kit.AFTER REPAIR
Bargraph 6 left hand side illuminated
Front left wheel sensor circuit
6
None.
NOTES
Fiche n° 53
If the resistance is correct, check and ensure the continuity of the connection between the sensor
connector and the computer connector:
- between one track of the sensor connector and track 7 of the computer connector,
- between the other track of the sensor connector and track 6 of the computer connector.
Also check the insulation between these connections.
Carry out a visual inspection of the sensor wiring and check the quality of the connection on the 31 track
computer connector.
If all the checks are correct, reconnect the computer and the wheel speed sensor then erase the computer
memory.
Exit fault finding mode(G13*) and switch off the ignition.
Switch the ignition on and replace the sensor if the fault reappears.
If the fault reappears after replacing the sensor, replace the computer.
Check the connection and condition of the sensor connections.
If the connector is correct, check the resistance of the sensor at its connector..
Replace the sensor if its resistance is not approximately 1.6 Kohms (1,6 Kohms ± 320 ohms).
38-7
Page 269 of 363

B76531.0
ELECTRONICALLY CONTROLLED HYDRAULIC SYSTEMS
Fault finding - Interpretation of XR25 bargraphs
38
ABS BOSCH
5.3
Erase computer memory(GO**).
Carry out a road test followed by a check with the XR25 kit.AFTER REPAIR
Bargraph 6 Right hand side illuminated
Front right wheel sensor circuit
6
None.
NOTES
Fiche n° 53
If the resistance is correct , check and ensure the continuity of the connections between the sensor
connector and the computer connector :
- between one track of the sensor connector and track 3 of the computer connector,
- between the other track of the sensor connector and track 5 of the computer connector.
Also check the insulation between these connections.
Carry out a visual inspection of the sensor wiring and check the quality of the connections on the 31
track computer connector.
If all the checks are correct, reconnect the computer and the wheel speed sensor, then erase the
computer memory.
Exit the fault finding mode(G13*) and switch off the ignition.
Switch the ignition on and replace the sensor if the fault reappears .
If the fault reappears after replacing the sensor, replace the computer.
Check the connection and condition of the sensor connections.
If the connector is correct, check the resistance of the sensor at its connector.
Replace the sensor if its resistance is not approximately 1.6 Kohms (1.6 Kohms ± 320 ohms).
38-8
Page 270 of 363

B76531.0
ELECTRONICALLY CONTROLLED HYDRAULIC SYSTEMS
Fault finding - Interpretation of XR25 bargraphs
38
ABS BOSCH
5.3
Erase computer memory(GO**).
Carry out a road test followed by a check with the XR25 kit.AFTER REPAIR
Bargraph 7 left hand side illuminated
Rear left wheel sensor circuit
7
None.
NOTES
Fiche n° 53
If all checks are correct, reconnect the computer and wheel speed sensor, then erase the computer
memory.
Exit fault finding mode(G13*) and switch off the ignition.
Switch on the ignition and replace the sensor if the fault reappears.
If the fault reappears after replacing the sensor, replace the computer.
Check the connection and condition of the sensor connections.
Check the connections at the intermediate connection under the body (R101).
If the connector is correct, check the resistance of the sensor at its connector. Replace the sensor if the
resistance is not approximately 1.6 Kohms (1.6 Kohms ± 320 ohms).
If the resistance is correct, check and ensure the continuity of the connections between the sensor
connector and the computer connector :
- between one track of the sensor connector and track 8 of the computer connector (via track B of the
connector under the body R101),
- between the other track of the sensor connector and track 9 of the computer connector (via track A of
the connector under the body R101).
Also check the insulation between these connections.
Carry out a visual inspection of the sensor wiring and check the quality of the connections on the 31 track
computer connector.
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Page 271 of 363

B76531.0
ELECTRONICALLY CONTROLLED HYDRAULIC SYSTEMS
Fault finding - Interpretation of XR25 bargraphs
38
ABS BOSCH
5.3
Erase computer memory(GO**).
Carry out a road test followed by a check with the XR25 kit.AFTER REPAIR
Bargraph 7 Right hand side illuminated
Rear right wheel sensor circuit
7
None.
NOTES
Fiche n° 53
If all checks are correct, reconnect the computer and the wheel speed sensor, then erase the computer
memory.
Exit fault finding mode(G13*) and switch off the ignition.
Switch on the ignition and replace the sensor if the fault reappears.
If the fault reappears after replacing the sensor, replace the computer.
Check the connection and condition of the sensor connections.
Check the connections at the intermediate connector under the body (R101).
If the connector is correct , check the resistance of the sensor at its connector.
Replace the sensor if its resistance is not approximately 1.6 Kohms (1.6 Kohms ± 320 ohms).
If the resistance is correct, check and ensure the continuity of the connections between the sensor
connector and the computer connector :
- between one track of the sensor connector and track 1 of the computer connector (via track D of the
connector under the body R101),
-between the other track of the sensor connector and track 2 of the computer connector (via track C of
the connector under the body R101).
Also check the insulation between these connections.
Carry out a visual inspection of sensor wiring and check the quality of the connections on the 31 track
computer connector.
38-10
Page 272 of 363

B76531.0
ELECTRONICALLY CONTROLLED HYDRAULIC SYSTEMS
Fault finding - Interpretation of XR25 bargraphs
38
ABS BOSCH
5.3
Erase computer memory(GO**).
Carry out a road test followed by a check with the XR25 kit.AFTER REPAIR
Bargraph 8 right or left hand side flashing
Front right or front left wheel sensor signal
Even if they are present at time of testing, these faults will always be declared by
BG 8 flashing on the left or right hand side.
To confirm their presence and therefore the need to apply the fault finding be-
low, carry out a road test. The fault is present if the bargraph illuminates during
the test.
If bargraphs 6 and 8 left hand side are both illuminated, deal with bargraph 6
first.
If bargraphs 6 and 8 right hand side are both illuminated, deal with bargraph 6
first.
NOTES
Fiche n° 53 8
Check the quality of the wheel speed sensor mounting (its position and that it is tightened to
recommended torque).Check the sensor / target air gap over one wheel revolution : 0.13 mm < air
gap< 1.96 mm. Check conformity of the target (condition, number of
teeth=26)
Carry out a visual inspection of the sensor wiring and check the quality of the connections on the 31 track
computer connector.
If all checks are correct, reconnect the computer and the wheel speed sensor, then erase the computer
memory.
Leave fault finding mode(G13*) and carry out a road test. Replace the sensor if the fault reappears.
If the fault reappears after replacing the sensor, it may be caused by an operating fault on a solenoid
valve and it is therefore necessary to carry out the hydraulic check of the solenoid valves with the XR25 kit
with command G03* or G04* (consult the section "Aid"). If the ten unlocking/locking cycles do not occur
on one of the wheels, replace the hydraulic assembly.
If the hydraulic assembly is not at fault, replace the computer.
Check the connection and condition of the sensor connections.
If the connector is correct , check the resistance of the sensor at its connector.
Replace the sensor if its resistance is not approximately 1.6 Kohms (1.6 Kohms ± 320 ohms).
38-11