JRMedved
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- Reaction score
- 45
- Thunderbird Year
- 2004
Thought I should share in the event others experience this issue...
I replaced the windshield washer pump in my 2004 Thunderbird last fall. After replacement, I noted that the hoses were relatively deteriorated and the nozzles on the cowl were plugged. I replaced the hoses and nozzles with new parts and all was working fine - for about a month or so.
Then I noted that there was a intermittent failure of the washer fluid spray. The wipers swept as designed when the wash function was enabled, but sometimes it would spray, sometimes it would not...no rhyme or reason. Since the wiper functionality worked fine in every other aspect (which ruled-out a fuse problem), I suspected perhaps it might be the result of a loose connection (at the pump motor). Since I'm pretty much homebound with nothing better to do (thanks, COVID-19!), I thought I would investigate and resolve this 'simple' issue.
Upon inspecting the washer pump connection it appeared to be tight. I checked the power feed circuit with a test light and got no light/voltage when activating the washer pump at the turn signal stalk on the multi-function switch (MFS). One thing that was unusual is that, according to the 2004 Ford Thunderbird Workshop Manual, this power circuit (circuit 30S-KA7) is supposed to be a RED wire with a white stripe (RED/white), but I noted that the connector had a YELLOW/violet wire. Circuit 31-KA7 (pump motor ground) is a black wire.
Concerned that I may have an open circuit, I checked both circuits from the washer pump motor to the wiper motor control module 12-PIN connector/Wiper Motor Jumper Harness (connector C110-9), which is located between the degas (radiator overflow) bottle and the power brake booster, and measured < 5Ω resistance both the power and ground circuit. So that ruled-out an open circuit (broken wire/loose connection) between the washer pump motor and the wiper motor control module.
Next, I removed the cover from the steering column to access the MFS. I checked for voltage between pins 2 and 5 (BLACK/red wire and the WHITE/violet wire) when the wash switch is activated. I noted 11.9-volts (good test). So, that ruled-out a problem with the MFS.
For all intents and purposes, there should be voltage to the washer pump when the switch is activated as no open circuits or switch failures are present. Further research indicated that the wiper motor control module has an integrated washer pump motor relay. Diagnostics indicate a failed internal washer pump motor relay in the module. This is UNUSUAL as this is the most unlikely failure of the system.
I've ordered a new motor assembly (Ford supercede part # 6L1Z-17508-AARM; Motorcraft part # WN778RM). I'll update this posting once I have received and installed the new motor assembly.
I replaced the windshield washer pump in my 2004 Thunderbird last fall. After replacement, I noted that the hoses were relatively deteriorated and the nozzles on the cowl were plugged. I replaced the hoses and nozzles with new parts and all was working fine - for about a month or so.
Then I noted that there was a intermittent failure of the washer fluid spray. The wipers swept as designed when the wash function was enabled, but sometimes it would spray, sometimes it would not...no rhyme or reason. Since the wiper functionality worked fine in every other aspect (which ruled-out a fuse problem), I suspected perhaps it might be the result of a loose connection (at the pump motor). Since I'm pretty much homebound with nothing better to do (thanks, COVID-19!), I thought I would investigate and resolve this 'simple' issue.
Upon inspecting the washer pump connection it appeared to be tight. I checked the power feed circuit with a test light and got no light/voltage when activating the washer pump at the turn signal stalk on the multi-function switch (MFS). One thing that was unusual is that, according to the 2004 Ford Thunderbird Workshop Manual, this power circuit (circuit 30S-KA7) is supposed to be a RED wire with a white stripe (RED/white), but I noted that the connector had a YELLOW/violet wire. Circuit 31-KA7 (pump motor ground) is a black wire.
Concerned that I may have an open circuit, I checked both circuits from the washer pump motor to the wiper motor control module 12-PIN connector/Wiper Motor Jumper Harness (connector C110-9), which is located between the degas (radiator overflow) bottle and the power brake booster, and measured < 5Ω resistance both the power and ground circuit. So that ruled-out an open circuit (broken wire/loose connection) between the washer pump motor and the wiper motor control module.
Next, I removed the cover from the steering column to access the MFS. I checked for voltage between pins 2 and 5 (BLACK/red wire and the WHITE/violet wire) when the wash switch is activated. I noted 11.9-volts (good test). So, that ruled-out a problem with the MFS.
For all intents and purposes, there should be voltage to the washer pump when the switch is activated as no open circuits or switch failures are present. Further research indicated that the wiper motor control module has an integrated washer pump motor relay. Diagnostics indicate a failed internal washer pump motor relay in the module. This is UNUSUAL as this is the most unlikely failure of the system.
I've ordered a new motor assembly (Ford supercede part # 6L1Z-17508-AARM; Motorcraft part # WN778RM). I'll update this posting once I have received and installed the new motor assembly.
NOTE: If you have a 2002 model year car, the wiper motor assembly has a 5-pin connector at the wiper motor control module (instead of a 12-pin connector), and therefore would call for a different part number. That said, I am not sure if the wire color-codes, connectors, or pin numbers described in this posting are applicable to that model year's wiper circuits.
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