Euro Headlight Wash/Wipe Troubleshooting: Difference between revisions
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Add Euro headlight wash/wipe Tech FAQ from forum t=56570 |
Add wash/wipe discussion tips from t=37798 (control unit, 4-lead motor, interval unit) |
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The service wash squirts a short burst of undiluted wash from the small reservoir nearest the cabin, then a longer squirt of diluted wash from the larger reservoir next to it, with the windscreen wipers. Then it squirts diluted wash on the headlights and runs the headlight wipers. | The service wash squirts a short burst of undiluted wash from the small reservoir nearest the cabin, then a longer squirt of diluted wash from the larger reservoir next to it, with the windscreen wipers. Then it squirts diluted wash on the headlights and runs the headlight wipers. | ||
The headlight wash/wipe only works with the headlights on. Headlights off, you only get windscreen wash. Some cars fire the headlight cycle every third press. Try five cycles with about 10 seconds between them before you assume it is broken. | The headlight wash/wipe only works with the headlights on. Headlights off, you only get windscreen wash. Some later cars fire the headlight cycle every third press; earlier cars (including Tusker's) do it every press. Try five cycles with about 10 seconds between them before you assume it is broken. | ||
'''Fuses.''' The wash/wipe system shares a fuse with the horns. If the horn works, it is not the fuse. | '''Fuses.''' The wash/wipe system shares a fuse with the horns. If the horn works, it is not the fuse. | ||
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# Remove the wiper blades, front grilles, and headlights. You can leave each motor on the headlight frame for testing. | # Remove the wiper blades, front grilles, and headlights. You can leave each motor on the headlight frame for testing. | ||
One motor has 3 leads (R, BL, BR) and the other has 4 (extra blue). Sources disagree on left vs right when "facing the car"; go by the extra blue lead. That blue wire is the washer-pump trigger — when the wiper hits a point in its rotation it puts 12 V on blue and the headlight washer squirts. The pump does not run the whole cycle; it pulses (every other rotation or so). The FAQ author later thought it was a timed burst rather than pulses. | |||
* Red — 12 V momentary | * Red — 12 V momentary | ||
* Black — 12 V constant | * Black — 12 V constant | ||
* Brown — ground | * Brown — ground | ||
* | * Extra blue — output to the washer pump | ||
To test a motor: fused lead from battery + to the '''black''' lead, ground the '''brown'''. Touch the '''red''' lead with another fused + for 2–3 seconds only. The motor should cycle about 30 seconds and shut off. The connector is awkward; a scrap of matching loom helps you avoid shorting pins. | To test a motor: fused lead from battery + to the '''black''' lead, ground the '''brown'''. Touch the '''red''' lead with another fused + for 2–3 seconds only. The motor should cycle about 30 seconds and shut off. The connector is awkward; a scrap of matching loom helps you avoid shorting pins. | ||
To test the washer-pump output on the | To test the washer-pump output on the 4-lead motor: meter between the '''blue''' lead and ground, then repeat the motor test. Voltage should rise from 0 V for a second or two. | ||
A dead motor is easiest to replace (part #s 61631369105 / 61631369106). | A dead motor is easiest to replace (part #s 61631369105 / 61631369106). | ||
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'''Service-wash switch.''' Remove the lower steering-column cover and unplug the stalk connector. Pressing the button should connect '''TS''' (BR/BL) and '''PS''' (BR/GY). Resistance should drop to zero. You do not need to pull the stalk or the wheel to test. If it fails, replace it (part # 61311369932 from 09/85). | '''Service-wash switch.''' Remove the lower steering-column cover and unplug the stalk connector. Pressing the button should connect '''TS''' (BR/BL) and '''PS''' (BR/GY). Resistance should drop to zero. You do not need to pull the stalk or the wheel to test. If it fails, replace it (part # 61311369932 from 09/85). | ||
'''Wash/wipe interval control unit.''' Big black box at the top of the fuse box. | '''Wash/wipe interval control unit.''' Big black box at the top of the fuse box. Regular windscreen washers can still work with a bad unit — the intensive / headlight circuit is separate inside it. A US-spec (non-euro) interval unit plugs in and lets you test everything except headlight wipers and intensive wash. Swapping a known-good euro unit is the other test. Tusker's own car still failed after a known-good interval unit; the fault was the headlight-cleaner control unit on the washer bottle (a very common failure — he and others went through more than one bad used unit). | ||
If every test above passes and it still does not work, walk through it again. | If every test above passes and it still does not work, walk through it again. | ||
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[[File:E28 Wiper Washer ETM.jpg|thumb|500px|none|ETM wiper/washer and heater washer jets.]] | [[File:E28 Wiper Washer ETM.jpg|thumb|500px|none|ETM wiper/washer and heater washer jets.]] | ||
== From the discussion == | |||
The published FAQ is a single post. Extra failure modes and the left/right motor clarification are from Tusker's earlier [https://forums.mye28.com/viewtopic.php?t=37798 Headlight wash/wipe troubleshooting (fixed)] thread ([[rs4pro3]], [[cgraff]], [[DRP535]], [[Rich Euro M5]]). The actual fix on that car was a replacement headlight-cleaner control unit. | |||
[[Category:Tech FAQ]] | [[Category:Tech FAQ]] | ||
