burpod
teh stallionz!!1
- Joined
- Nov 27, 2004
- Location
- cape cod, ma
- TDI
- 82 rabbit vnt ahu, 98 jetta vnt ahu, 05 parts car, 88 scirocco.. :/
big question: does the stock AHU (or ALH for that matter) AC/fan setup disable the coolant fans from running when the car is travelling at higher speeds? looking at the mk3 bentley wiring diagrams, i don't see any possible way it could do this but maybe i'm missing something. so is it correct that no matter what speed the car is travelling, the coolant fans are always running when the AC is switched on?
what i would like: does anyone have any suggestions to add a speed sensitive switch/relay so that the fans don't run constantly? i would think that going 40+ mph, the running fans are totally unecessary. seems like a waste, especially on long summer highway drives - plan to take my car on a cross-country roadtrip in june. i found this- lingenfelter speedbased switch. it's a bit pricey but looks like it would work. any other ideas that might be cheaper? perhaps some sort of cheap mechanical switch that activates a basic relay. i'm going to assume i can find a way to do this and leave an accessible provision for it in the wiring so i can finish up and get the car drivable again (gotta put the engine back together too lol). BTW, i have no plans of re-installing the stock fan control module, see below.
history:
when i rebuilt the car about 9 years ago, i completely removed AC - everything, wiring and all. never figured out exactly why, but it wasn't working at the time and i didn't care) i sort of "custom wired" the CE2 fusebox and redid everything. at the time, i rarely ever used AC and installed an fmic instead and simplified the wiring. a lot has happened since then and now i want my AC again - got two kids now (almost 2 and almost 5) and it's essential
so i'm in the process of installing it - with my current FMIC that is a great fit and a 12x24 universal parallel flow AC condenser. i'm going to have to make a couple custom lines, but that should be relatively easy if i can get someone to weld a couple fittings on aluminum pipes. the HVAC box with new evaporator is back in the car now, as well as working recirc flap.
i modified the fuse/relay-box so that i could use #1 relay position (AC) to run the high speed fans - flexalite twin fan. i believe low speed runs one fan (no relay), and high temp/speed activates the relay (a #100 with 2 87 outputs) to run both fans. i also had previously wired the AC button to manually run both fans - in the event the coolant fan speed switch failed at an inopportune time. so i don't use the big honky vw coolant fan control module, just a single relay in the fusebox.
what i would like: does anyone have any suggestions to add a speed sensitive switch/relay so that the fans don't run constantly? i would think that going 40+ mph, the running fans are totally unecessary. seems like a waste, especially on long summer highway drives - plan to take my car on a cross-country roadtrip in june. i found this- lingenfelter speedbased switch. it's a bit pricey but looks like it would work. any other ideas that might be cheaper? perhaps some sort of cheap mechanical switch that activates a basic relay. i'm going to assume i can find a way to do this and leave an accessible provision for it in the wiring so i can finish up and get the car drivable again (gotta put the engine back together too lol). BTW, i have no plans of re-installing the stock fan control module, see below.
history:
when i rebuilt the car about 9 years ago, i completely removed AC - everything, wiring and all. never figured out exactly why, but it wasn't working at the time and i didn't care) i sort of "custom wired" the CE2 fusebox and redid everything. at the time, i rarely ever used AC and installed an fmic instead and simplified the wiring. a lot has happened since then and now i want my AC again - got two kids now (almost 2 and almost 5) and it's essential
so i'm in the process of installing it - with my current FMIC that is a great fit and a 12x24 universal parallel flow AC condenser. i'm going to have to make a couple custom lines, but that should be relatively easy if i can get someone to weld a couple fittings on aluminum pipes. the HVAC box with new evaporator is back in the car now, as well as working recirc flap.
i modified the fuse/relay-box so that i could use #1 relay position (AC) to run the high speed fans - flexalite twin fan. i believe low speed runs one fan (no relay), and high temp/speed activates the relay (a #100 with 2 87 outputs) to run both fans. i also had previously wired the AC button to manually run both fans - in the event the coolant fan speed switch failed at an inopportune time. so i don't use the big honky vw coolant fan control module, just a single relay in the fusebox.
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