Another Crank No Start | OBD2 No Comm + Xmas Tree Inst Panel w/Bonus ‘It hasn’t run in months’

Based on the part number yours is double cab short bed with tow package.

Take your pick, just make sure the part numbers match.
https://www.hollanderparts.com/used...mbly,-crew-cab-(4-dr),-short-box,-tow-package

 

Sweet - thank you for making that considerably easier than if I'd tried that on my own.

For the airbag sensor - it would actually show up in Techstream when everything was plugged in.

1.) Is there a chance it isn't fried or since it interfered with communication overall it should just be replaced?
2.) If replacing, are there suggestions for it, as my searches turned up a number of avenues to have it reset, not replace.
3.) Is getting a replacement from a salvaged truck that has been in an accident even possible or feasible? Seems like a working one that is used would be few and far between.
4.) Can it just be bypassed?






More part numbers:
CDFE5I004N
233285-104
89170-04580

 

If it's talking and not affecting communications with other stuff it may be ok, the B1650 means there's codes in the Occupant Classification ECU so you need to check that and see what those are.
The B1661 is probably because the Meter isn't connected.

If it does end up needing one being a critical safety component I'd probably go new, looks like they are around $350-400.

 

No doubt! That whole ordeal could have ended so bad. I never actually hit the concrete, but was bruised up a bit and for the life of me didn't know why until it hit me (pun intended) earlier today. I'd grabbed one of my canes when I headed back outside, went down the stairs and hit that wheel on the second step. With that cane - which I'm not accustomed to carrying by the way - I broke out into some kind of accidental kung fu, as I flailed about proceeding to kick my own ass apparently. If only the security camera were still at that door. It had to be hilarious to see once I realized I wouldn't be yelling out "Help, I've fallen and I can't get up"

The cane use is only temporary and helps me to step over or around some of the junk in the workshop Never thought of it as a weapon lol

 

The AIRBAG SENSOR only seems to talk when the BRAKE ACTUATOR ASSEMBLY (SKID CONTROL ECU) is connected.

With everything connected, the CENTER AIRBAG SENSOR ASSEMBLY has always reported for duty, along with the Immobilizer and the Tire Pressure Monitor. I've never seen the BRAKE or the COMBO METER (old one) connect. The replacement Brake part is on the way. I ordered the entire assembly, but to answer our question about whether that assembly comes apart, lookie at what I stumbled across:




Ebay Link


It looks like it will come apart, but I'm not sure if that is enough to prevent a re-enactment of Spindletop in my workshop I won't stress over it just yet.

I decided to wait on the Airbag sensor to see if by some fluke the canbus gods will have mercy on me and allow everything to connect when the brake part is replaced. I did get the new Combo Meter installed. The meter has the same indicator lights on or flashing as the other one, but they are probably valid since some of that stuff is disconnected. I can see it on Techstream though, which is a first.

I still have the blasted Blower Motor connector to fix, the DLC to reassemble, and that clip by the alternator, plus the trailer lights, re-wrap some wiring, and basically put the whole damn thing back together and that makes me tired thinking about it.

Although moot now, I did get all of the scope videos uploaded.

https://www.youtube.com/@RageAgainstMyMachines/videos


I'll be back in a day or 2 or few as I venture to somewhere other than my office or workshop.

Thanks again for all of the help and for being patient with me.

 

Interesting I'm not 100% sure which line the scan tool talks to it on, if it talks to it on CAN or on the K line (SIL terminal) (Pin 7 of the DLC) or if it tries on CAN and falls back to the K line if it can't talk on CAN.
I may plug in my Launch scanner that shows network topology tomorrow and see what it shows.

Can you talk to the Occupant Classification ECU?

I know it comes apart, the question is whether or not the screws will come out so it can be taken apart. The nice thing is you can plug it in first before doing anything and make sure it talks.

One thing at a time, we'll get there. I mean we went from a totally braindead truck to a truck that runs and talks, now we just gotta work the rest of the bugs out.

I'll have a look later and give some feedback.

No worries I think you have had more patience than anyone, most people in your shoes would have given up on it long ago.

 

Dang. Freaking impressive. Well done OP and @Dm93

 

Ok so according to my tool the SRS talks on the K-line so makes sense it still talks when the CAN line is messed up.

 

I'm drooling over that technology you have there that prob cost at least 1 arm and 1 leg.

For the K-Line: Something still is wonky though (and it could easily be me) because the SRS will only work when the ABS is connected. Maybe it would work with the just the Steering or the just the Yaw Rate sensor plugged in; I didn't try. I just happened to go in the order of when the ABS was disconnected, the Airbag also dropped. The scope reading (?) from both of those looked like they were jacked, which is why I figured both would need replacing, but then I got to thinking "hey, that Airbag communicated just fine before", at least with TechStream. In the manual, the wiring for the airbag looks like it connected to CAN-H and CAN-L, which I need to read up more on how K-Line would relate to that before I confuse myself.

I can go out and confirm with details on the ABS to Airbag - would there be anything specific i could do or collect for it?

I don't recall ever seeing an Occupant Detection module with any of the Techstream scans. There was a reference to OD in the Airbag codes, but the driver seat is out of the truck and the passenger seat has something unplugged under it as well. I just caught that a couple of nights ago and need to ask why he unplugged it. Seems like it was related to a seat heater or something. I actually didn't realize there was a separate ECU for it - is it called something else that I can search in the FSM?

The Brake Actuator thing should be here tomorrow!! I have a poncho ready.

 

Not super crazy, I got it on sale for $969. There's plenty cheaper options out there that do all the same functions but don't have the network topology.
I wanted one with topology, it can make troubleshooting no-coms easier on these newer vehicles that have 20+ modules running on 3 or more different networks.

Yea the SRS is on both, according to service info and my scan tool it talks to the scanner on the K-Line. It's curious that it won't talk with the ABS Disconnected though (I may have to do an experiment).

As for the K-Line (Toyota does not call it this, on the wiring diagrams it's labeled SIL) it's just another communication bus but it's single wire and does not use terminating resistors. On 2nd gens it's only used for module diagnostics and for the modules to talk to the scan tool, it's not used for module to module communication.
The TPMS, SRS, Occupant Detection, and Immobilizer modules are on the K-Line.

I'm not sure what we could check there, the CAN signal looks like garbage with the SRS connected weather or not the ABS is connected. I think get the replacement ABS plugged in and see what we can talk to.

It's called the Occupant Classification ECU in service info, it's under the passenger seat so I bet that's what's unplugged.
It's job is to tell the airbag system if someone is sitting in the seat or not and how much they weigh so it can decide whether or not to deploy the passenger airbag in a collision.

 

That topology is the cool part Maybe Hantek manufactures something along the lines lol. I honestly had no idea these super hi-tech diag tools existed, which considering that just over a year ago I had no clue that the vehicles themselves had this level of tech, I guess it would only make sense. I could use one of the handheld scanner things, but thought it was all just "OBD". Heck - I was reading that it's possible to do packet captures on a car using Wireshark which had me all excited, but I need to stay focused. Truck repair now...Wireshark later.

So some of the modules - like the SRS Airbag - use both CAN and SIL? SIL for what you described above, and CAN for maybe module to module?

There were very few references to SIL in the FSM; periodically the SIL light on the BoB would light up a lot like something was using it. That was my famliarity with it. With Techstream showing the SRS/TPMS/IMMO modules consistently, I thought 'maybe' those were using SIL for something, but then the airbag threw me off because I thought it was using CAN.

Looking in the FSM at CAN COMMUNICATION > DIAGNOSIS SYSTEM (Attached) under Check Installed Systems, there's a chart with all the modules that (I assumed) use CAN, but then below it "Hint: Vehicle with ABS do not use CAN communication" and at this point I'm crosseyed.

We can come back to the whole CAN/SIL thing another time. For now, I'll just accept that SIL and CAN both exist, single wire, no resistors, and are utilized somewhere in this truck

Nice. The truck knows how much I weigh So I stand corrected on this Occupant ECU. It looks like it was there on 12/31, but hasn't made regular appearances in Techstream though. It was always the same 3 modules TPMS/IMMO/SRS. I didn't disconnect anything on passenger side myself, but next time I'm out there I'll get a better look at it.




The brake part shipped Fedex, and Fedex absolutely, positively, is not reliable in this area. I'm not knocking all of FedEx, just the delivery in our particular area. I expect it will be here Monday after 2 days of saying it would be here by end of day. Yay!!

 

Topology on aftermarket tools just recently became a thing (there's currently only a handful of them that have it) like in the past 2 or 3 years, it's a good thing though as the complexity of vehicle network and electrical systems has increased exponentially in the past 10 years. 2nd gen Tacoma's are relatively ancient technology compared to what we're dealing with on today's vehicles.

As far as capturing and analyzing data packets that's beyond my scope, all I need to know is if it'a communication or not and if it's not why it's not. I don't need to know what it's saying although I could see that being helpful in certain unusual cases where a module isn't seeing correct data from another module, many newer (20+) vehicles are going to some form of encryption on their communications so packet analysis would be all but impossible.

I'm pretty sure based on the research I've done and your findings that the SRS uses CAN for module to module communication and K-Line (SIL) for scan tool communication and diagnostics.

As far as I know there is no module to module communication on the K-Line (SIL), it sit's at 12v unless the scan tool is talking to one of the modules on it.

I see that, looking at diagrams I have to assume that's for trucks that have only ABS (like many 05-08 trucks) and not VSC or traction control, all US spec 09+ Tacoma's have ABS/VSC/Traction Control so not sure why they left that bit in there.

Hopefully it's just unplugged.

It was like that around the holidays here with packages in the mail, had a couple that sat at the distribution hub for over a week.

 

Two 12 packs of Diet Coke is enough to make the seat belt light come on on my truck.

And I picked up a back prob kit today/ No more T-pins for me.

 

Today's FedEx message is different- it says it is Out for Delivery. When it gets here, I can plug the new Brake Actuator in at the connector (not removing old one) just to make sure it works, correct?

 

Yes.

 

The part arrived yesterday, and it’s the right part, but in the wrong condition. It looks like it took a detour through the Mississippi River on the way here. I'm not going to harp on it because I sent photos to the vendor, they apologized immensely and immediately issued a refund, leaving me to keep the part. Now I have one I can disassemble. If it was meant to come apart, and things look OK on the inside, I'll see about testing it. I'm not too hopeful. If I come across a catfish or hydrilla, I'll order another. I'll take some pics and notes to post, and if it wasn't meant to come apart, it can save time and effort for someone else in the future.


I almost made was an attempt to separate it here at my desk before realizing what type of surprise might be on the inside. I have it in a tub now. Whew.

 

Good God. That’s horrible.

Not all of that happened in shipping.
Did they even inspect it before sending it?

It’s good you got a refund at least.

 

I honestly didn't think any of it occurred from shipping, but spouse pointed out an update to tracking indicating a new label, and the box had a note saying it was repackaged. I may not have been too far off with my river analogy as this thing was completely filled with water and mud, and it smells. It was gurgling when I handled it, so I set it outside overnight to drain.

I tinkered to the point where I lost my patience. The mindset changed to "even though it CAN come apart, was it designed to?". My answer to that was "doesn't matter because I'm over it and am taking a prybar or something to it". I'll reverse engineer the disassembly to disassemble it the wrong way to see if there is a right way. I don't have my answer yet, but the prybar got it open. The new part ships tomorrow. Hopefully UPS or something.

This video helped me understand that the big heavy cylinder is an electric motor and not a bunch of brake fluid

https://www.youtube.com/watch?v=IKi5O3ZlSu4

And last, behold, the river-bottom brake actuator. No catfish this time.

 

It's been underwater for sure.
I'd hate to see the truck it came out of.

 

This is the truck it came out of lol:



or better yet, maybe this one:



I forget how she (FedEx support) worded it, but there was inclement weather in that area and most likely the package fell off the truck at one of the hub stops.

This is the photo of what I bought...




...which is the same part I got with the same writing and tag on it. The seller refunded me, so I guess I'll let her know everything in case she wants to pursue a refund from FedEx.




I guess I have a week to read up on bleeding brakes and replacing this thing as a whole unit. I look forward to my first 'torque' if applicable.