The codes you have indicate an open circuit for the TFT sensor. It is recommended that you actually test them with an ohm meter to prevent un-necessary repairs that could eventually lead to future problems. Overlaying a circuit is acceptable if done properly and you seem to understand that. Begin with testing from the PCM to the transmission connector. If the harness is chaffed and one of the TFT wires is damaged it is likely that other wires are also affected. If that is the case, I certainly would want to pinpoint the location of the open circuit. Also, this sensor receives a 5-volt reference signal from the PCM which should be verified as well. Not a fan of repairing internal transmission harnesses.
05 6.0 TFT Sensor Issue Temp Trans Transmission 5r110W
Hello Guys I'm back with a issue again. 😏 Truck has been driving fine and all of sudden...the dreaded tow/haul light flash and check engine light appeared. Didn't have scan tool on me, so I checked trans Temp (with hands) and it didn't appear to be hot which was important to me before continuing driving. The trans gauge didn't fall to Cold level and was above it but not at normal position once warmed up. Got home put my scanner on it and showed a P0710 and P0713. Figured my TFT sensor was shot and thought this was going to be an easy fix for me.....but it never works out that way for me. Lol. Ran down to the Dealer and picked up a new Motorcraft TFT. Replaced it, reset codes, fired her up and bammnn....lights flashing and same thing. Truck still drives fine but I don't want to run it like this. I'm going to backprobe PCM and also Trans Connector starting at the PCM first with trans connector unplugged and see if I have any issues there then connect trans connector back to internal trans connector and see what my readings are there....does that sound right? 🤔. My question is if I find a bad wire whether it be from PCM to Trans, or Trans Internal from External plug to Internal, can I just run some new wires without having to replace the whole harness? If so, what is the best way to tie into the circuit ...butt connectors, sealed epoxy connectors, silicone sealed ends on connector then heat shrink tubing? That's my idea for the external side of it from PCM to Trans Harness obviously I would run the wire through a cable protector as well and zip tie out of harms way. Also if I find a problem on from the outside trans harness to TFT sensor internal side, whats the best route there since I'm inside the trans with fluids etc? Please help me out here, I want to do this right one time and call it done. I know some will say to replace whole internal trans harness but I don't have the extra funds right now to drop $300 on the harness....thought I'd pull some Mcgiver stuff but in a quality way if possible. Let me know your tricks and what you have done that has worked for you with no issues. All your help is greatly appreciated and look forward to talking. Thank you. Cheers Guys! 🥂
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Thanks Ford Doctor 👍🙏 Appreciate the response and info. When testing from the PCM to Trans connector to measure resistance do I remove the trans connector with 10mm bolt in it and test from PCM to the Trans connector with bolt meaning pin from PCM to opposite pin on trans connector? I<<<<<if so, i think I need a set of long probes to be able to reach at both locations. Or do I leave it plugged in and do my test straight from PCM to internal harness TFT circuit?<<<<I'm thinking this won't tell me my strength of the first harness from PCM to Trans bulkhead connector but I could be wrong. Also, how do you find where the short or open is, what's your route on that? I would rather not rip open the whole harness to find where it's at....what do you do or what type of tools do you use to locate the short or open?
And yes your 100% right, if there was a short or open in the circuit I would want to find where in the loom it is so I could double check surround wires to see if they are affected as well. Also, I'm not a big fan of doing hack work on wires like inside the trans internal harness but wanted to get your guys advice on it to see if you guys have done repairs on internal harnesses before without having to buy whole harness. My another idea I had if I had a bad TFT tire on internal harness was to de-pin it from trans harness and run a new TFT wire run with pin to harness but that was an idea just didn't know if it will work with damage.
Also a few months back my scan tool brought up 2 codes that never appeared before which were, P0528 Visctronic drive fan VDF speed circuit malfunction and also a P0470 EBP sensor circuit malfunction. The EBP tubes were removed and cleaned completely no blockages and new motorcraft EBP sensor was installed. Now that I'm thinking about it, do these 2 above circuits run in the same loom as the problem I'm having now with my TFT sensor? 🤔
Also Ford Doctor, when I replaced my TFT sensor, I noticed when I plugged it in even though it clicked seems like there was some play left to right on the connector is that normal? Or should it be tight no movement?
The sensor fits a little loose so it's normal.Also Ford Doctor, when I replaced my TFT sensor, I noticed when I plugged it in even though it clicked seems like there was some play left to right on the connector is that normal? Or should it be tight no movement?
Ok. Thought it wouldn't fit loose but glad I know that's normal. Did you see my post #5?The sensor fits a little loose so it's normal.
I'm pretty sure they don't run through the same loom. They definitely don't come from the same PCM connector. i've attached diagrams for an '05 for both Dual and Single alternators (props to @djmaguire).Also a few months back my scan tool brought up 2 codes that never appeared before which were, P0528 Visctronic drive fan VDF speed circuit malfunction and also a P0470 EBP sensor circuit malfunction. The EBP tubes were removed and cleaned completely no blockages and new motorcraft EBP sensor was installed. Now that I'm thinking about it, do these 2 above circuits run in the same loom as the problem I'm having now with my TFT sensor? 🤔
-jokester
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I'm pretty sure they don't run through the same loom. They definitely don't come from the same PCM connector. i've attached diagrams for an '05 for both Dual and Single alternators (props to @djmaguire).
-jokester
Awesome! Thanks for the one page layout of the wiring schematic Jokester! I have a single alt and looked it up and looks like it just loops through the TFT resistor and comes back on the signal wire which I'm assuming the PCM translates and knows how many degrees the TFT is by the resistance in the sensor and data. Appreciate the help. Thanks for taking the time to respond. 👍🥂🥂
Today's Update:
Hello guys and Happy Friday! Thanks for all you who have chimed in on this situation I'm dealing with . Worked on my truck today and did some electrical testing. When I removed the trans bulkhead connector, it had what appeared to be dielectric/electrical grease on it, is that normal from factory/Ford dealer. I owned this truck for 12 years now and I'm the only one who's worked on it since I have owned it. I will post pictures of connector. I also cleaned it with electrical spray cleaner both bulk head external and internal wiped clean and air compressor dried both before plugging back in to see if that fixed problem before continuing and it did not. I will list it below tests i ran:
-PCM plugged in and probed at Trans Bulkhead and got 5v ref sig.
-PCM #26 (TFT) to Trans Bulkhead #18 (TFT) got .1-.2 ohms.
-PCM #30 (SigRtn) to Trans Bulkhead #22 (SigRtn) got .1-.2 ohms.
-TFT Sensor Connect #1 to Internal Bulk Pin #18 got .1-.2 ohms
-TFT Sensor Connect #2 to Internal Bulk Pin#22 got .1-.2 ohms.
When doing the below (2) tests the Ford Manual states this: Measure the Resistance between TFT Sensor Pins# 18 and #22, and ground. I assumed that meant from one pin to ground and then the other pin to ground so that's what I did. Am i wrong? The next 2 tests are the ones I did following the above procedure.
-Trans Internal Bulk #18 to Ground got O.L on meter.
-Trans Internal Bulk #22 to Ground got O.L on meter.
-TFT Sensor pin#1 to pin#2 got 24k at ambient temp correct as far as chart goes (Just put in new Motorcraft TFT sensor when all this first happened a few days ago that didn't fix it).
what do you guys think the problem is judging by what I posted? Swap internal harness? Or can I fix the 2 TFT wires with new ones and heat shrink seal them both? Also when replacing the internal harness, I'm assuming you have to replace the gasket behind the trans valve body correct?
Hello guys and Happy Friday! Thanks for all you who have chimed in on this situation I'm dealing with . Worked on my truck today and did some electrical testing. When I removed the trans bulkhead connector, it had what appeared to be dielectric/electrical grease on it, is that normal from factory/Ford dealer. I owned this truck for 12 years now and I'm the only one who's worked on it since I have owned it. I will post pictures of connector. I also cleaned it with electrical spray cleaner both bulk head external and internal wiped clean and air compressor dried both before plugging back in to see if that fixed problem before continuing and it did not. I will list it below tests i ran:
-PCM plugged in and probed at Trans Bulkhead and got 5v ref sig.
-PCM #26 (TFT) to Trans Bulkhead #18 (TFT) got .1-.2 ohms.
-PCM #30 (SigRtn) to Trans Bulkhead #22 (SigRtn) got .1-.2 ohms.
-TFT Sensor Connect #1 to Internal Bulk Pin #18 got .1-.2 ohms
-TFT Sensor Connect #2 to Internal Bulk Pin#22 got .1-.2 ohms.
When doing the below (2) tests the Ford Manual states this: Measure the Resistance between TFT Sensor Pins# 18 and #22, and ground. I assumed that meant from one pin to ground and then the other pin to ground so that's what I did. Am i wrong? The next 2 tests are the ones I did following the above procedure.
-Trans Internal Bulk #18 to Ground got O.L on meter.
-Trans Internal Bulk #22 to Ground got O.L on meter.
-TFT Sensor pin#1 to pin#2 got 24k at ambient temp correct as far as chart goes (Just put in new Motorcraft TFT sensor when all this first happened a few days ago that didn't fix it).
what do you guys think the problem is judging by what I posted? Swap internal harness? Or can I fix the 2 TFT wires with new ones and heat shrink seal them both? Also when replacing the internal harness, I'm assuming you have to replace the gasket behind the trans valve body correct?
Hello Guys. Did some more testing today with the time I had and trying to figure this all out. Here is the tests below.
-Trans Bulk connected PCM pins #26 to #30 got 43k ohms. Temp outside was 60 degrees and pan has been off since yesterday no fluid.
-Trans Bulk pins #18 to #22 jumpered to one in other with paperclip got .4 ohms measured at PCM connector pins #26 and #30.
-When PCM Harness is disconnected from PCM my scan tool still shows -40 degrees on Trans Temp....same thing when PCM is plugged in??
- Key off- Trans Bulk and PCM connected backprobed Pin#26 at PCM to ground 6.24k ohms. Same pin to power got O.L then 0.0 ohms back and forth. When I watched my DMM to Sound with ohms I got O.L on both which I thought was weird as I thought Ohm setting and Sound with Ohms on DMM were the same just one has sound?
The following tests below are with Trans Bulk and PCM connected!
-Key on backprobed PCM pin#26 to ground/power both 00.0 ohms
Key on DMM set to volts backprobed PCM#26 to ground 8.01v and power 4.02v
Key off backprobed PCM#30 TO ground batt post 11.6 ohms and to ground bolt on truck 00.6 ohms....don't know why the ohms are different from battery post and ground bolt of truck. Thought they were all connected in sync?
Key on PCM#30 to ground post 137 ohms and to ground bolt on truck 82.2 ohms.
Key off PCM and trans bulk connected measured from PCM pin#26 to pin#30 got 43k ohms temp was 60 degrees outside.
Another test I performed just to see data values was removed PCM trans connector and probed at the mating #26 and #30 pins inside PCM computer. Tests are below:
-Pin#26 to ground. 2.4 Mohms-4.5 Mohms
-pin#26 to power O.L
-Pin #30 to ground O.L
-Pin #30 to power O.L
I'm confused on this whole matter. Please let me know what you guys think with the data I have been posting. Thanks for your time and help. Talk soon. -Steve
-Trans Bulk connected PCM pins #26 to #30 got 43k ohms. Temp outside was 60 degrees and pan has been off since yesterday no fluid.
-Trans Bulk pins #18 to #22 jumpered to one in other with paperclip got .4 ohms measured at PCM connector pins #26 and #30.
-When PCM Harness is disconnected from PCM my scan tool still shows -40 degrees on Trans Temp....same thing when PCM is plugged in??
- Key off- Trans Bulk and PCM connected backprobed Pin#26 at PCM to ground 6.24k ohms. Same pin to power got O.L then 0.0 ohms back and forth. When I watched my DMM to Sound with ohms I got O.L on both which I thought was weird as I thought Ohm setting and Sound with Ohms on DMM were the same just one has sound?
The following tests below are with Trans Bulk and PCM connected!
-Key on backprobed PCM pin#26 to ground/power both 00.0 ohms
Key on DMM set to volts backprobed PCM#26 to ground 8.01v and power 4.02v
Key off backprobed PCM#30 TO ground batt post 11.6 ohms and to ground bolt on truck 00.6 ohms....don't know why the ohms are different from battery post and ground bolt of truck. Thought they were all connected in sync?
Key on PCM#30 to ground post 137 ohms and to ground bolt on truck 82.2 ohms.
Key off PCM and trans bulk connected measured from PCM pin#26 to pin#30 got 43k ohms temp was 60 degrees outside.
Another test I performed just to see data values was removed PCM trans connector and probed at the mating #26 and #30 pins inside PCM computer. Tests are below:
-Pin#26 to ground. 2.4 Mohms-4.5 Mohms
-pin#26 to power O.L
-Pin #30 to ground O.L
-Pin #30 to power O.L
I'm confused on this whole matter. Please let me know what you guys think with the data I have been posting. Thanks for your time and help. Talk soon. -Steve
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