Bronco638 Posted September 12 Share Posted September 12 My 1980 F-150 now has the 'new' drivetrain installed; 302 w/SROD. The truck had the 351M/C6 from the factory. I am trying to figure out what wiring remains from when the original drivetrain was removed. Specifically, I'm trying to find the wires for the water temperature sending unit (red w/white stripe) and the oil pressure sending unit (white w/red stripe). Here's what on the driver's side wheel well in the engine compartment: The connection in the yellow box is what I'm trying to figure out. There's three wires there. I'm pretty sure two of them are the ones for which I'm searching: water - R/W and oil - W/R. What I'd like to know is what the other wire is (and maybe what connector that is). The third wire appears to be red with green or brown stripe but it's very hard to tell. I've been looking in the EVTM and thought that the connector might be C325 but the EVTM says that connector is round with eight wires (unless it means eight wires total? And, the EVTM gives varying locations for that connector). What's even more odd is that all of the wires, going INTO the male connector, have different color codes from the wires LEAVING the female connector. The two wire connector, in the red box, is for the DuraSpark module I believe. Can anyone verify that those are the two wires (temp sender & pressure sender) for which I'm looking? Any chance anyone can ID the third wire? TIA Link to comment Share on other sites More sharing options...
viven44 Posted September 12 Share Posted September 12 Ford changed the coloring over the years.. Purple/Pink, etc etc... 1980 was also the one year wonder in wiring. I have the EVTM as well and it does say 8 terminals!! Has to be a mistake.. The most fool proof way is to disconnect the connector and just confirm with probes and a multimeter.... (Measure resistance between the sending unit wire and the guessed wire, etc). I always insert a paper clip in the terminals and then clip a probe to that. The green wire should be for tachometer, should go to ignition coil negative. The one in the red box does appear to be the DS-II. White wire should receive battery voltage while ignition is in Run and Red wire should receive battery voltage while cranking (you can also test this with probes/multimeter).... this gets swapped at the module if you had the module (Red becomes white and white becomes red!!) Link to comment Share on other sites More sharing options...
Bronco638 Posted September 12 Author Share Posted September 12 Ford changed the coloring over the years.. Purple/Pink, etc etc... 1980 was also the one year wonder in wiring. I had forgotten about that. A wiring diagram, while hard to read, may be the key here. I have the EVTM as well and it does say 8 terminals!! Has to be a mistake.. That connector has four wires on one side (the side with the green wire) and three on the other (visible in the image posted). Also, the three wires that go out of frame have cut ends. There's no terminals that would provide a clue as to what they were attached to. You'd expect to see the 90* push on connectors for those two sending units. The most fool proof way is to disconnect the connector and just confirm with probes and a multimeter.... (Measure resistance between the sending unit wire and the guessed wire, etc). I always insert a paper clip in the terminals and then clip a probe to that. The issue is that neither the temp. sending unit nor the pressure sending unit has any wires currently connected to them. The green wire should be for tachometer, should go to ignition coil negative. The green wire doesn't come out of that connector, it only goes into it. I do have the coil "horseshoe" and the part of the DuraSpark harness that goes from the module to the distributor. I believe the tach wire is part of that harness. I forgot to mention that the 302 has an HEI distributor. I don't think the 351M did (it used the DS module). The one in the red box does appear to be the DS-II. White wire should receive battery voltage while ignition is in Run and Red wire should receive battery voltage while cranking (you can also test this with probes/multimeter). Could I use these wires and connect them to the HEI BAT lug as the power source for the distributor? ... this gets swapped at the module if you had the module (Red becomes white and white becomes red!!) That I recall from my old '85 Ranger with the DS II. Geez Ford..... Link to comment Share on other sites More sharing options...
viven44 Posted September 12 Share Posted September 12 Ford changed the coloring over the years.. Purple/Pink, etc etc... 1980 was also the one year wonder in wiring. I had forgotten about that. A wiring diagram, while hard to read, may be the key here. I have the EVTM as well and it does say 8 terminals!! Has to be a mistake.. That connector has four wires on one side (the side with the green wire) and three on the other (visible in the image posted). Also, the three wires that go out of frame have cut ends. There's no terminals that would provide a clue as to what they were attached to. You'd expect to see the 90* push on connectors for those two sending units. The most fool proof way is to disconnect the connector and just confirm with probes and a multimeter.... (Measure resistance between the sending unit wire and the guessed wire, etc). I always insert a paper clip in the terminals and then clip a probe to that. The issue is that neither the temp. sending unit nor the pressure sending unit has any wires currently connected to them. The green wire should be for tachometer, should go to ignition coil negative. The green wire doesn't come out of that connector, it only goes into it. I do have the coil "horseshoe" and the part of the DuraSpark harness that goes from the module to the distributor. I believe the tach wire is part of that harness. I forgot to mention that the 302 has an HEI distributor. I don't think the 351M did (it used the DS module). The one in the red box does appear to be the DS-II. White wire should receive battery voltage while ignition is in Run and Red wire should receive battery voltage while cranking (you can also test this with probes/multimeter). Could I use these wires and connect them to the HEI BAT lug as the power source for the distributor? ... this gets swapped at the module if you had the module (Red becomes white and white becomes red!!) That I recall from my old '85 Ranger with the DS II. Geez Ford..... - deleted - Link to comment Share on other sites More sharing options...
viven44 Posted September 12 Share Posted September 12 - deleted - I have the 1980 EVTM. The only references to C325 are as follows... I am seeing a green wire in your pic so I'm not sure R/LB coming in from ignition run --C325-- R/LB going out to ignition coil + R/YH coming in from Fuse 2 via S404 --C325-- R/YH going out to Anti-diesel Throttle solenoid positioner If you have gauges R/W coming in from water temp sending unit --C325-- R/W going to water temp gauge via C208 W/R coming in from oil pressure sending unit --C325-- W/R going to oil pressure gauge via C208 If you have warning light W/R coming in from oil pressure switch -- C325 -- W/R going to onto oil pressure warning indicator light via C208 Link to comment Share on other sites More sharing options...
Bronco638 Posted September 12 Author Share Posted September 12 I have the 1980 EVTM. The only references to C325 are as follows... I am seeing a green wire in your pic so I'm not sure R/LB coming in from ignition run --C325-- R/LB going out to ignition coil + R/YH coming in from Fuse 2 via S404 --C325-- R/YH going out to Anti-diesel Throttle solenoid positioner If you have gauges (I do) R/W coming in from water temp sending unit --C325-- R/W going to water temp gauge via C208 W/R coming in from oil pressure sending unit --C325-- W/R going to oil pressure gauge via C208 I found the exact same thing. What's difficult is that the four wire colors that come into the connector in the image are not identifiable. I can't tell if they're red, orange or pink (aside from the green and white wires). Those four also seem to be of different gauges. The green wire appears to be 12 or 14 gauge while the other three are 16 or 18 gauge. I went out to the garage and took a closer look. Those four wires appear to be (in no particular order); green, white, red/white stripe and orange (maybe with yellow hashes?). On the opposite side of that connection, the white wire corresponds to white/red, the red/white corresponds with red/white and green corresponds with red/??? stripe. The orange wire has no corresponding wire on the other side of the connection. At this point, I think I've found the water temperature sender (R/W) and oil pressure sender (W/R) wires. The color coding seems to be the same for F Series as well as 80s Rangers. I am curious as to what the third wire color code and function is. Link to comment Share on other sites More sharing options...
viven44 Posted September 12 Share Posted September 12 I have the 1980 EVTM. The only references to C325 are as follows... I am seeing a green wire in your pic so I'm not sure R/LB coming in from ignition run --C325-- R/LB going out to ignition coil + R/YH coming in from Fuse 2 via S404 --C325-- R/YH going out to Anti-diesel Throttle solenoid positioner If you have gauges (I do) R/W coming in from water temp sending unit --C325-- R/W going to water temp gauge via C208 W/R coming in from oil pressure sending unit --C325-- W/R going to oil pressure gauge via C208 I found the exact same thing. What's difficult is that the four wire colors that come into the connector in the image are not identifiable. I can't tell if they're red, orange or pink (aside from the green and white wires). Those four also seem to be of different gauges. The green wire appears to be 12 or 14 gauge while the other three are 16 or 18 gauge. I went out to the garage and took a closer look. Those four wires appear to be (in no particular order); green, white, red/white stripe and orange (maybe with yellow hashes?). On the opposite side of that connection, the white wire corresponds to white/red, the red/white corresponds with red/white and green corresponds with red/??? stripe. The orange wire has no corresponding wire on the other side of the connection. At this point, I think I've found the water temperature sender (R/W) and oil pressure sender (W/R) wires. The color coding seems to be the same for F Series as well as 80s Rangers. I am curious as to what the third wire color code and function is. The only thing I can suggest is to use a in-line 1 amp or 0.5 amp fuse and connect those wires being guessed as for sending units to ground... if the gauges move to max then you have found the answer.. The mystery of that 3rd wire is to be determined still... Link to comment Share on other sites More sharing options...
Bronco638 Posted September 12 Author Share Posted September 12 The only thing I can suggest is to use a in-line 1 amp or 0.5 amp fuse and connect those wires being guessed as for sending units to ground... if the gauges move to max then you have found the answer.. This is assuming that there's a power source (battery) in the truck, right? As of now, there isn't one. The mystery of that 3rd wire is to be determined still... Yeah... Link to comment Share on other sites More sharing options...
Bronco638 Posted yesterday at 12:33 PM Author Share Posted yesterday at 12:33 PM I think I have this figured out. I took me looking thru my spares piles (yes, plural) at home and in my storage unit. I came across the DuraSpark II harness, from the DS2 module to the distributor. It's not in the best shape but still good enough to ID wire codes and provide a refresher on how those wires hooked up. I'm almost positive that the 'mystery' wire is the R/LG that runs to the positive side of the coil. If I mate it up with the short stub coming out of the coil 'horse shoe', the wire color code looks the same and the angle of the cut thru the wire itself, matches. However, this is not what I want to use to power the HEI. That seems to be the W/LB H wire that originally powered the DS2 module. Now I need to figure out how to connect a wire from the distributor's tachometer lug to the wiring harness so the tach works. Link to comment Share on other sites More sharing options...
Gary Lewis Posted yesterday at 12:45 PM Share Posted yesterday at 12:45 PM Glad you are getting it figured out. The Dark Green/Yellow wire goes to the tach. Link to comment Share on other sites More sharing options...
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