ABS issues (C1408-C1416)

All,


I'm having some ABS light issues, and wanted to get feedback, as some of you may have experienced the same.

My truck: 2018 TRD Off-road Double cab, 4x4 (locker) Auto
Tire Size: 315 75 16, on SCS F5s (hub centric) (have been installed for 35k miles)
Gear ratio: 529s. Have had installed for 35k miles.
Suspension: 2.5 oldman emu lift
After market rear and front extended braided brake lines

Now onto the issue. ABS, Traction control, basically all the lights are on. The Codes that it is throwing are C1408, and at times C1416. These come and go.

What have I done for remediation? Ive already replace the left rear (drivers side) sensor, after doing this, the code went away for around 200 miles. Then came back. Figured it may have been the Skid control wire, located under the bed, because of the C1416 code. I replace this wire. The codes went away for around 200 miles.

As I was driving downhill, using engine braking, with no codes on, I noticed that the speedometer skipped. It dropped and the climbed to what i would say is normal speed. then the codes reappeared. I went to toyota, and we put it on the tech stream. All 4 wheel sensors are reading speed correctly. While on the drive, the codes went away.

Im getting tired of throwing money at this problem, so if anyone has experienced any of these issues, id sure appreciate your feedback.

C1416:

One of the following conditions is met:
An open in the sensor signal circuit of a malfunctioning area occurs 255 times or more.
At a vehicle speed of 20 km/h (12 mph) or more, noise occurs in the sensor signals of a malfunctioning wheel 75 times or more within 5 seconds.
At a vehicle speed of 10 km/h (6 mph) or more, noise occurs once per rotor rotation for 15 seconds or more.

C1408:

Either condition is met:
An open in the speed sensor signal circuit continues for 0.5 seconds or more.
With the IG1 terminal voltage at 9.5 V or higher, the sensor power supply voltage decreases for 0.5 seconds or more.


Trouble areas

C1416

Rear speed sensor RH/LH ----replaced left wheel speed sensor
Skid control sensor wire ---replaced skid control wire
Speed sensor circuit
Rear speed sensor rotor RH/LH (Rear axle hub and bearing assembly RH/LH)
Skid control ECU (master cylinder solenoid)

C1408

Rear speed sensor RH/LH----replaced left wheel speed sensor
Skid control sensor wire---replaced skid control wire
Speed sensor circuit
Skid control ECU (master cylinder solenoid)



TL;DR entire thread - Toyota found it was the Frame Wiring Harness that had been damaged, causing the codes to come and go.

 

It sounds like the exact same problem that I had with my 2001 4Runner. The ABS, parking brake, trac ctrl lights were all on, my speedometer stopped working, and in turn the odometer stopped working. Occasionally while driving first thing in the morning when it was cold, the speedometer would work for a little bit then stop once the engine heated up a bit. Sadly, we couldn't find a solution to the problem without paying more than the car was worth. Which is one of the reasons I now own a Tacoma. I took it to the Toyota place an they said we would have to replace the whole ABS system and computer, which would cost about $4,000. Took it to numerous other mechanics to see if they could figure out a way to do it cheaper. One place said they could do it, and said they would order the part. When we tried to call back about getting it put in, they wouldn't even pick up the phone every time we tired calling. So I ended up driving it for over 2 years with no speedometer. My main mechanic said there was nothing mechanically wrong with it, it was just all in the computer. I would say take it back to Toyota and ask what is the problem and how much it would be to fix it, otherwise you may be just throwing money into replacing random parts hoping it fixes it like I did.

 

Notice any chewed wires up in cabin or rear? I'd test continuity all the way back to ecm and start wiggling wires to see if you can make it drop out. The intermittent issue may be pointing to that or tonering damage.

 

So my speedo and and tac are all working normally except for that "jump" I mentioned. But the lights are the same, except for the parking brake.

That was something I did straight away, because if I can get home insurance to replace this I would. I didnt see any chewed up wires, and the picture above is from were we removed the bed. I also found zero blown fuses.


a

 

Lights are still on, no issues going into 4 wheel high or 4lo, exept the dash says 4wd failure.

But I can hear the click of the the transfer case and feel the difference in driving.

Locker wont engage, and traction control cant be taken on or off

 

ABS sensor or wire. After that, check battery..
After that, check for vermin.

 

Nothing in diff (fresh oil change). Appears sensor was covered in something when removed. Re installed. Code appears to stay away (150 miles so far)

 

Codes have returned, taking it into dealer on the 26th, they are opening a case with toyota corpo

 

C1408 points to an intermittent wiring issue. Need to check all wires, contacts, and connectors between the LR wheel speed sensor and skid control ECU. Something has likely been pinched, pulled, damaged, corroded, etc.

 

Rear harness fails on these, the lifted trucks with long travel shocks tend to wear them out quickly, I always try to bend down the bracket for the full travel of the harness.

 

Ive already replaced the rear harness from under the bed to the rear, and the left sensor.

 

I also get the intermittent code of c1416

 

Instrument cluster could be going bad.

 

lol no i dont think thats it. Id be more prone to believe the ABS ecm module before that

 

Alrigh then

 

If you have faulty circuit, C1408, then by definition you'll have faulty output, C1416. It's more likely C1408 causes C1416.

ECU's get blamed a lot for issues but are the least likely part to actually fail. It happens, but very rarely without some kind of obvious abuse.

 

Ive looked for a wiring diagram to locate how the wires are run under the cab from th ABS control module, but even the Toyota master tech didn't have them. I cannot source them online either. I'm just having a difficult time understanding where i could have pinched a wire. I know that its direct, there are zero fuses that interact with the abs system. Leading me to believe it is either a wheel bearing in the rear, or the ABS CM. When I pulled the sensor, there was brown shit all over the tip of it. I cleaned it off, and reinstalled it. My rear gear fluid is brand new (less than 2k miles). If it isnt the rear wheel bearing, what do you think the chances are that it may be that stuff is getting into my hub because I have wheels that have no hub covers, or that maybe I have a faulty axle shaft seal?

 

Left my truck at toyota for the last day.

Got a call from them this morning. They are saying it is a frame wiring harness, at a cost of 1200 bucks for the part, 25 hours of labor.

Any thoughts?

 

I think that makes sense.

1. Create an account with either All Data DIY or Mitchell's and for ~$50 you can have three years of access to ALL of the repair data & wiring diagrams for your vehicle. You can also do this through Toyota, but it's a LOT more expensive.
2. Buy/borrow/rent a DVOM, incandescent test light, some back probes and ideally, a megger.
3. Using the diagrams from Mitchell's / All Data, determine which wires run from the ABS Module to which sensor.
4. Disconnect from the ABS module and/or ECM, and from the sensors
5. Perform fault tests on each sensor; if no faults move on to 6.
6. Conduct a visual inspection of the whole harness; look for abrasions, wear in the loom, tape, etc. Look for sharp bends, pinch points... if/when you find one, open up the harness isolation the ABS conductors and inspect (with a magnifying glass if necessary)
7. If sensors and visual pass, then start checking each conductor for continuity, voltage drop, and continuity with ground.

If all of that fails, then over to the dealer for repairs; if they call harness and that doesn't fix it, then it's 99.99999999999999999% the ABS Module, and the money for the harness job gets credited to that one.

Or... live with it.

 

Thanks. I appreciate the walk through and steps.

After speaking with the master tech, he told me that Toyota has had 3 cases like this since 2016.

1 truck was out in California, and it was a full LT truck.

2nd case was actually caused by road debris

And mine is number 3.

In all three cases the harness was replaced, and the issue was resolved. The tech told me he did do a voltage drop test, and a continuity test, with a full disconnect from the ABS Control module.

He read a large spike along the harness. I've done a visual inspection of the harness (in the locations in which I can see) and there isnt any apparent wire pinches, or damage from rodents.

I'm going to have the harness replaced instead of worrying about a drop line possibly being a snag hazard in the future.

After the work is completed, I'll follow up if this doesnt help remediate the issue