Pinpoint Tests

The following tests give detailed information on component fault diagnosis.

Wiper Motor:

1. Wiper Motor
a. Check +12 V from fuse F6 in LH engine bay fuse-box is present at connection LS009/005 when column stalk switch is in position 1.
b. Check +12 V from fuse F6 in LH engine bay fuse-box is present at connection LS009/006 when column stalk switch is in position 2.
c. Check for sound earth connection from harness pin LS009/004.
d. Check resistance across motor terminals, readings of approximately 1.3 Ohm (normal speed winding) and 1.4 Ohm (fast speed winding) should be achieved.

Wiper Motor Relay:

2. Wiper Motor Relays
a. Check +12 V from fuse F6 in LH engine bay fuse-box is present at ON/OFF relay connections LS048/002 and LS048/005 when column talk switch is in position 0.
b. Check +12 V from fuse F16 in RH heelboard fuse-box is present at FAST/SLOW relay connection LS049/002 when column stalk switch is in position 0.
c. Check +12 V from fuse F6 in LH engine bay fusebox is present at ON/OFF relay connection LS048/003 and FAST/SLOW relay connection LS048/004 when column stalk switch is in position 1.
d. Check for +12 V at FAST SLOW relay connections LS049/001 and LS049/005 when column stalk switch is in position 2.
e. Check continuity between connections LS048/003 and LS049/003, LS0481001 and FC001/027 and LS049/001 and FC008/011.
f. Check resistance across relay coils between pins 1 and 2 (both relays). A value of 65 Ohm should be recorded in each case. A lower value indicates coil short circuit.

Wiper Motor Park Switch:

3. Wiper Motor Park Switch
a. Check continuity between connections FC002/001 and LS009/001, and LS009/003 and earth.
b. Check that switch is normally open when wipers are not in use

Column Stalk Switch:

4. Column Stalk Switch
a. Check continuity between switch connection FC008/001 (wash/wipe) and Body Processor Unit (BPU) connection FC002/014.
b. Check continuity between switch connection FC008/002 (intermittent wipe) and BPU connection FC002/039.
c. Check continuity between switch connection FC008/008 (slow & flick wipe) and BPU connection FC002/047.
d. Check continuity between switch connection FC008/011 (fast wipe) and FAST/SLOW relay connection LS049/001, Ensure correct polarity of test instrument to avoid damage to diode FC061.
e. Check continuity between switch connection FC008/006 and ground.
f. Operate switch to all positions checking corresponding continuity to ground across each relevant pin (as identified above.).

Screen Wash Pump And Relay:

5. Screen Wash Pump and Relay
a. Check +12 V from fuse F13 in RH engine bay fuse box is present at pump connection RS025/002 when column stalk switch is pressed inward.
b. Check for sound earth from pump connection RS025/001.
c. Check resistance across pump terminals. A value of approximately 3.73 Ohm should be achieved.
d. Check continuity between pump connection RS025/002 and relay connection RS002/005.
e. Check continuity between BPU connection FC001/034 and relay connection RS002/001.
f. Check continuity between RH engine bay fuse-box connection RS001/004 and relay connection RS002/003.
g. Check coil resistance across relay connections 1 and 2, a value of 65 - 125 Ohm should be achieved. A lower value indicates coil short circuit.

Screen Wash Jet Heater:

6. Screen Wash Jet Heaters
a. Check +12 V from fuse F10 in RH engine bay fuse box is present at ambient air temperature sensor connection BR007/001.
b. Check +12 V at heater element connections Pl071/001 and Pl072/001 when ambient air temperature sensor is closed, i.e. temperature below +4 °C.
c. Check heater elements resistance. A value of 68 Ohm should be achieved in each case.

Power Wash Pump And Relay:

7. Power Wash Pump and Relay
a. Check +12 V from fuse F17 in RH engine bay fuse box is present at pump connection RS026/002 when column stalk switch is pressed inward.
b. Check for sound earth from pump connection RS026/001.
c. Check resistance across pump terminals. A value of approximately 2 Ohm should be achieved.
d. Check continuity between pump connection RS026/002 and relay connection RS020/005.
e. Check continuity between BPU connection FC001/040 and relay connection RS020/001.
f. Check continuity between RH engine bay fuse-box connection RS006/001 and relay connection RS002/003.
g. Check coil resistance across relay connections 1 and 2, a value of 65 - 125 Ohm should be achieved. A lower value indicates coil short circuit.