Crusty Rusty Leaky Squeaky 67 Step

[Ramjet51]

Great thread and I’m being tutored by an incredible forum. Great talents. I found your thread, started reading and just really liked the bumper treatment, even was late for a doc appointment because I got so engrossed in the reading. So closed the iPad down and couldn’t find the tread again for hours and hours....why??....I was mainly searching for a SWB thread and never thought it would be a “Step”....got back on the read and now I’m up to date, what a great thread.....don’t know if it’s been said, but ground loops in signals can occur if you ground both ends of a shielded cable. I’ve always practiced this, maybe Chris will chime in...

[Aberdare]

Vic:
Even though it has been past the specified warranty period... If your local dealer wants to continue to covet the business of people like yourself, regardless of the warranty period... they may give you some serious consideration for a replacement WITH a software upgrade. Of course if you ask nicely (with your wallet poised to head out the door)... word will get around quickly whether that word is pos(+) or neg(-) will be up to them of course.

Here in Winnipeg the dealers are all the same... if your vehicle is more than 10 years old, they just don't want your business... and some of the dealers are worse than others... but it never hurts to ask of course - the worst they're going to say is NO then watch you AND your wallet walk out the door.

Abe

[Vic1947]

Originally Posted by Ramjet51

Great thread....don’t know if it’s been said, but ground loops in signals can occur if you ground both ends of a shielded cable. I’ve always practiced this, maybe Chris will chime in...

I know I have some twisted pairs, but no shielded cable in the GMPP harness from what I can see. Thanks for the read!

Originally Posted by Aberdare

... and some of the dealers are worse than others... but it never hurts to ask of course - the worst they're going to say is NO then watch you AND your wallet walk out the door.

We'll see how it goes, Abe. I'm guessing at some point I could be looking at new parts or service fees for repairing mine.

I got kinda worked up a couple of times today, only to suffer a letdown. Pin 17 on the TCM connector plug is labeled SPEEDO OUT and the schematic showed an orange/white wire coming out of it. Realized there's no wire in that cavity, just a dummy pin. Then I took a closer look at the schematic and despite the label, it shows the pin as unconnected. It also occurred to me that the cruise control wiring harness has a pigtail that splices it into the electronic pedal. The CC also requires an input from the orange SPEEDOUT wire. I'd disconnected the speed wire to the CC early on after talking to the first tech at GM, but never removed the pigtail going to the pedal, so I did that as well, but to no avail... still nothing.

So, my latest line of thought is that the VSS signal coming from the tailshaft may actually need to go to the ECM instead of the TCM. The following text is from the I-sheet that came with the package.

Vehicle Requirements
Vehicle Speed Input - optional
The ECM is programmed and looking for 40 pulses per revolution
typical for automatic transmissions. The LS Control System harness
is designed to plug into the output speed sensor of 4L60 & 4L80
Transmissions, which have a 40 pulse output. NOTE: If you are using
the CP Supermatic Connect and Cruise Transmission Control
System, the vehicle speed input must be plugged in.

These things (I think) I know:

1) The speed out cavity in the TCM plug is blank and I see no other speed signal coming out of the TCM according to the schematic. So apparently the TCM isn't tasked with sending out a speed signal to the speedo.

2) The orange SPEEDOUT wire is connected to a brown wire via the bulkhead connector which comes out of the ECM on pin 39 of the blue (C1) ECM plug.

3) The gray (C3) ECM plug uses pins 66 & 67 for the VSS TOSS high and low.

4) I see no path whereby the TCM takes the signal coming from the transmission tailshaft (VSS TISS) connector and passes it thru the TCM and out to the ECM. Admittedly, I don't have a full set of schematics for the ECM, only the pinouts, but I haven't stumbled across the way the signal might move between the two controllers.

5) Somehow the ECM has to get a VSS signal if it's going to send the square wave out thru the bulkhead connector to the unterminated orange wire that feeds the speedo. Which brings me back to the above quote from the I-sheet.

Tomorrow it looks like I'll be back on the phone. Maybe I'll get a tech who will give me so useful pointers. Will post up what I find.

[Xeen]

I know this is frustrating for you but on the bright side you are gaining knowledge about GM electronics, enough that you will be able to help other people that are running into issues and asking for help with diagnostics, so something good will come out of all this trouble in the end.

[a.c.ward]

vic, we did a connect and cruise on a customers car and experienced similar speedo problems, we used Dakota Digital gauges, so I cant help with the gauges, but check out the following information I found on line:
Circuit # Position Wire Gage Color Description
818 D 22 Brown Vehicle Speed - Out

description in manual of what the brown wire does:
Vehicle Speed (BROWN) – This is a non scaled output for use with
auto-scaling speedometers and will not function unless a vehicle
speed sensor (VSS) is connected to the ECM through the VSS wire
in the harness.

this in on the 12 pin connector engine side of the harness. I connected this brown wire to the DD box and speedo worked, maybe worth a try for you.

maybe check out also

circuit #121 position 25 wire gauge 22 wire color white engine speed bulk head pos c on the blue C1 engine connector, also shows speed out.

if you have any further questions or need to talk this thru, you should still have my number, we talked thru the Vintage Air hardlines once before, if you need my number PM me.

AC

[Vic1947]

When I got up this morning, I sat on the edge of the bed for a long while and Kathy asked if I'd had a rough night. I had and proceeded to tell her I was ready to throw in the towel and move on. But after moping around for awhile, I called GM Powertrain again and got yet another tech. He, like the others, said they weren't supposed to help customers. After whining about the expense of this package and how it's promoted as "plug and play" it got sort of tense, but he finally said that they see this problem a lot and it's always because the user has the wrong plug in the tailshaft sender. I was surprised because the VEH SPD plug in the ECM harness was nowhere near long enough to reach the trans. But he swore that was what needed to be hooked up.

So I took a deep breath and isolated the twisted pair from the sensor going into the TCU and snipped them. Then spliced the ends coming from the tailshaft sender into the VEH SPD wires out of the ECM harness. And, by golly, that did the trick. I now have a working speedometer and more importantly, the transmission shifts thru all 4 forward gears and the speed displays on the laptop calibration software. I can now start reassembling all the stuff I had to take apart while troubleshooting. Thanks to all for bearing with me while I wandered around in the fog and for all the suggestions.

This whole thing with the GM techs reminds me of a Brit talking to an American. They're both speaking English... but not really.

[Jason7121]

Glad to hear you got the issue fixed Vic. Did that correct your flickering engine light as well?

[Vic1947]

Originally Posted by Jason7121

Glad to hear you got the issue fixed Vic. Did that correct your flickering engine light as well?

Nope, but my buddy Mike is coming over tomorrow with the good scanner. I'm sure if there's a computer issue, it can find it. But I'm inclined to think it's noise since it seems to increase with engine speed. If the scanner comes up empty, I may try a noise filter on the circuit.

[Ol Blue K20]

Glad to hear it's figured out. You have a lot more patience than I do.

[Xeen]

OMG I would have been madder than all hell if after all that I found out that the correct plug was too short to reach the transmission and it wasn't mentioned in the instructions, I would have went ballistic on GM and chewed so much ass they would have had to bolt on a new ass afterwords.
I'm glad someone finally helped you even if it was reluctantly.
Chin up Vic you are on the home stretch now.

[Vic1947]

Originally Posted by Ol Blue K20

Glad to hear it's figured out. You have a lot more patience than I do.

Lemme tell ya, I was nearing the end of my rope.

Originally Posted by Xeen

OMG I would have been madder than all hell if after all that I found out that the correct plug was too short to reach the transmission and it wasn't mentioned in the instructions...

They could have done a lot better job of explaining that part of it on the I-sheet. I guess if you've done a C&C swap like this or work with crate setups at a dealer, you'd be more likely to understand the jargon. When I run across something new, I usually wind up going WTF is that? Then googling it, only to find that ten different people refer to it in five different ways. The good news is that it's working and I can move on to other stuff. Only seven weeks to the LMC C10 show.

[Aberdare]

Vic:
Good to hear that you've sorted out the speedo issue without having to resort to banging heads against walls (including your own). So, the GM Tech had the audacity to actually say to you "We're not supposed to do this, but..." ?

If I had a GM Employee stating that to me... I'd be having a one-sided conversation with his manager, as the guy is packing up his desk. That kind of NEGATIVE customer Service would have me madder-than-a-hatter, well that kind of Customer Service doesn't happen if you want to keep customers... Just saying.

Once again - glad you got it sorted out!
Abe

[rustytruck50]

Great news, Vic!! It frustrates me to no end when I'm looking for info on something like that, I know people who know technical things like that and I either get a deafening silence or get dealt the "I have the info & knowledge, but for some reason I feel like being a jerk and I'm going to dangle it in front of you, taunt you with it until you pay me exorbitantly and or you get exasperated and leave" card....I've never grasped that kind of customer service.

[swamp rat]

Knowing I'd be no help at all I bit my lip on the sideline hoping this would all get sorted out, what an ordeal to say the least, Glad your getting back on track!

[sduckworth13]

Originally Posted by swamp rat

Knowing I'd be no help at all I bit my lip on the sideline hoping this would all get sorted out, what an ordeal to say the least, Glad your getting back on track!

I’m with you Mike. I’m happy you got it all figured out Vic.

[Low Elco]

Cue the Halleujah Chorous! Yaay Vic! Time to lay some rubber!

[knomadd]

That's great news, Vic! I'm glad you didn't throw in the towel. Now that it's operational, you'll likely be pleased with the end result, so hang in there. You're almost at the end of the tunnel (I was going to say done, but lets face it, they're never really "done").

[Vic1947]

Originally Posted by Aberdare

... So, the GM Tech had the audacity to actually say to you "We're not supposed to do this, but..." ?

Yes they did, Abe, and not just one but all three. It's like as soon as they found out I wasn't a dealer or certified independent shop, the wall went up. They have a code you have to put into the automated phone system. If you don't have a code, you use a generic 999999 entry. So they probably know from the get go that you're on the outside looking in.

Originally Posted by rustytruck50

...I've never grasped that kind of customer service.

Me either, but it's very frustrating. All they had to do was to say, "There are two plugs that will fit the sensor on the tailshaft. One comes out of the TCM harness, the other is out of the ECM harness. If you have a Supermatic 4L65E, use the one from the ECM harness... not the TCM harness." It took three calls and a large helping of sarcasm to get that info.

Originally Posted by swamp rat

Knowing I'd be no help at all I bit my lip on the sideline hoping this would all get sorted out, what an ordeal to say the least, Glad your getting back on track!

Thanks, Mike, what matters is knowing all the guys that follow this thread have my back.

Originally Posted by sduckworth13

I’m with you Mike. I’m happy you got it all figured out Vic.

Thanks, Scott. I may call to see if you can drop by this weekend to help put the hood on. I have a funeral to attend on Thursday, so I'll lose a day, but if the truck goes back together quickly, I could possibly be ready.

Originally Posted by Low Elco

Cue the Halleujah Chorous! Yaay Vic! Time to lay some rubber!

You bet, Chip. It sounds like it would do so with ease. I need to get the fan control module back from Derale. It's not working so I sent it to them on Monday. They should have it tomorrow and do some forensics. Hopefully it will be back soon. Not that I think I need it as cool as it is. Even without the fans running, the temp hasn't climbed over 195.

Originally Posted by knomadd

That's great news, Vic! I'm glad you didn't throw in the towel. Now that it's operational, you'll likely be pleased with the end result, so hang in there. You're almost at the end of the tunnel (I was going to say done, but lets face it, they're never really "done").

True that about never being done, Duane. I'm feeling pretty positive right now. Mike came over today and put the GM Tech 2 scanner on the OBDII port and all the live data and history showed no issues whatsoever. Still don't understand the flickering MIL on the dash, but it's low priority at the moment. I calibrated the speedometer today using the instant cal feature. With the C&C transmission software communicating with the TCM, I set the correct gear ratio and tire size into the calibration file. I then put the trans in 3rd gear and set the virtual speedo on 30mph. Pressed the calibration button for two seconds and voila! the Classic speedometer read the same as the virtual one. Upshifted to fourth and compared speeds at 65mph and they were the same. With the speed around 50mph, I set the cruise control and it worked like a champ. So I'm in the process if buttoning up the interior again and getting back on the punch list.

[AKC]

Most excellent! Glad you got it going and moving on...

[sduckworth13]

Cool Vic. I’d be glad to assist anytime.

[Low Elco]

Man, that's great. Isn't the "going Forward" feeling good? Been fighting the same thing on the barn, and just rounded a couple corners myself. Onward!

[Vic1947]

Originally Posted by AKC

Most excellent! Glad you got it going and moving on...

Me too!

Originally Posted by sduckworth13

Cool Vic. I’d be glad to assist anytime.

I'm counting on it, Scott.

Originally Posted by Low Elco

Man, that's great. Isn't the "going Forward" feeling good? Been fighting the same thing on the barn, and just rounded a couple corners myself. Onward!

Building a shop out back is a big project with lots of details, Chip. I'm anxious to see it when you're fully moved in and operational. You don't really want me around any kind of building construction until it's 100% finished, though.

Quick note: When I contacted GM Powertrain several times over the last week, they sent me a survey via email. I filled it out yesterday and politely gave them an earful. This morning, shortly after 8AM, I received a call from a supervisor at the Tech Center. The purpose of the call was to reinforce that the techs did nothing wrong by telling me what they did. He again raised the "liability" issue as their rationale. I'm at a loss as to what kind of liability they might be exposed to by simply giving someone technical assistance, but that's their story and they're sticking to it. I did tell the guy that there seems to be a disconnect between their marketing and customer support. Maybe they should put in a disclaimer saying, "This stuff should work, but if it doesn't, you're on your own."

[Aberdare]

Originally Posted by Vic1947

Maybe they should put in a disclaimer saying, "This stuff should work, but if it doesn't, you're on your own."

More like... "The Engineer who designed this is way to smart for us here at tech support to understand... so we want to make you feel stupid too, until you get mad and belittle us into doing our jobs."

[Vic1947]

The Truxedo tonneau cover went on today. Fit very nicely given all the hacks to the bed. I've got an 18" spare wheel/tire on the way which I'll bolt to the floor of the bed. It may get in the way a little bit when I'm hauling sheetrock, but I figure if I carry a spare, I'll never need it.

[rustytruck50]

Originally Posted by Vic1947

The Truxedo tonneau cover went on today. Fit very nicely given all the hacks to the bed. I've got an 18" spare wheel/tire on the way which I'll bolt to the floor of the bed. It may get in the way a little bit when I'm hauling sheetrock, but I figure if I carry a spare, I'll never need it.

The tonneau cover really sets the truck off!
I keep seeing little details, like the rear bumper....subtle and eye catching all at the same time
..hauling sheetrock...you're such a kidder, right?