4hi flashing, no cruise control, and only 2wd works

Hello, new member and just bought my wife a 2008 Sequoia 5.7 4x4 with 180k miles and rust free for a bargain. The prior owner didn’t want to deal with the 4wd problem and after doing some research on here I though it should be a small enough issue that it is worth picking up and fixing. The previous owner said they were driving along in 2wd and the 4hi light just started flashing rapidly. Since then the transfer case shifter has been inoperable and they drove it as it was for a couple months with the display constantly flashing only 4hi. The cruise control doesn’t work which I hope is a related issue

So, I’ve read most of the transfer case actuator threads and was expecting to take the top cover of the actuator off and find a rusty motor but unfortunately that was not the case. Let me give a run down of what I have tried and fair warning that I’m a modest mechanic at best...
1. Used a code reader and got no codes.
2. Listened to the transfer case actuator as the switch was turned and heard nothing.
3. Check all fuses, transfer case electrical connections and front diff electrical connections. I turned the ignition on, cab switch to 4hi and used a voltmeter on the lower transfer case connector and got a cycle of varying voltage on most of the points. I’m not sure if this is correct or if it should be a consistent voltage signal. Maybe it means the cab switch is bad or it is some sort of computer issue?
4. Open up the top of the transfer case actuator. The vent hose was still in tact (although somewhat rotten) and it looked like new in there. I used a battery and alligator clips to attempt to move the motor and it turned freely in both directions. I then re assembled the actuator hopefully correctly and still no dice.

I am beginning to think I am going to have to take a trip to the dealer or a more experienced mechanic to help diagnose this issue. I bought the rig for $7,500 so I have some room for repair funds but we all know keeping the repair fund down leaves more money for fuel and mods. Hopefully worst case scenario is me picking up a transfer case from a salvage yard and muscling that beast up there. Otherwise the truck runs great and it just needs a deep cleaning and a level/wheels and tires to counter the strong soccer mom vibe.
Thanks for any help

 

Have you checked the ABS/wheel speed sensors? I broke one on the farm and 4wd was inoperable and a lot of dash lights were on.

Is the ABS or VSC lights on?

 

any other button not working on the steering wheel beside cruise control ? thinking clock spring for anything on the steering wheel.

 

Yes, only light on the dash is a rapid flashing 4hi. I haven’t checked the speed sensors since all the threads with that issue had other lights flashing as well but it’s worth a try.

 

I second this IF the ABS and VSC lights are on. Had the same exact issue on a 5th gen 4Runner;I had a broken wheel speed sensor harness. And nothing worked including 4x4. Additionally there were no codes.

 

All other steering wheel controls work but they’re only audio related. Now that you mention it the windshield washer isn’t working but the wipers are. I figured the tank was empty but just checked and it’s not. The cruise control light does illuminate on the dash but when you set it as you’re driving nothing happens.

 

This is very likely to be related to a broken wire somewhere. I hit a part of the harness replacing the steering rack in my 4th gen 4Runner and had the exact same symptoms you have when one wire popped out of a plug. You could have something as simple as a worn or broken ABS sensor wire on one of the wheels.

I would get a scanner plugged in and drive around a monitor all your wheel speeds just to be sure that they are all registering properly. You may also find that while there are no basic check engine codes, a slightly more expensive code reader that can get into the ABS system may give you all the information you need. If you find that one of your front speed sensor harnesses is bad, it's not a bad idea to just replace them both.

 

if the horn stops working at some point that is a given for clock spring fyi. Just monitor it.

 

I broke a rear wheel speed wire, the rear right where it goes across the top of the axle. Resoldered it together and got rid of the lights on the dash. Can't remember if my 4x4 was out or not.

 

Thanks for all the input. I will be sure to report the fix whenever I find it so anyone else with this issue can benefit. Tonight I cleaned and regreased all four wheel speed sensors and followed the wiring until it went into the loom or out of sight and didn’t find any breaks or damage. Tomorrow I will look it over with more detail considering that seems to be the consensus that is my issue. I unplugged the battery overnight just incase that would reset anything. I’m not sure if it does with these trucks.

I wish that chart helped point me somewhere but since only my 4hi is flashing my rig doesn’t meet any of those scenarios. I need to find a friend with a better scan tool. I borrowed one from an auto part store and it felt like one of my toddler’s toys.

 

What part of the world do you live in? Sometimes you may find someone close by with such a tool, or a highly recommended shop that can at least diagnose it properly for you.

 

I’m in Bend, OR. The land of Yotas.

 

I experienced erratic behavior with a past vehicle, a 99 Ford F-150 4x4. It had electrical problems of many symptoms: Irratic wind shield wipers, 4x4 light flashing, other idiot lights flashing, and then it graduated to not starting, draining the battery for no apparent reason. Read the Ford forum with many other people experiencing same problems and worse. Others had their Ford stop dead on the highway. Anyways you get the drift. I traced it to that era of build having a slight leak in the windshield. I did find water by the petals, and exploring the wiring under the dash I found a drip onto the ECU. There was a TSB on it from ford, but since I never was notified on it. No recall of course. I replaced the windshield and it solved the problem. I sold it and bought a Tundra. Lost confidence in the old ford as I go off into the mountains where no cell phones work, so it was a no brainer to get rid of the old truck.

That’s my story, so I hope you find your problem. I ha e a lot of education and experience working on electrical problems, but mine was a doozy I hope never replicates in the Tundra.

 

I’m doing some reading tonight and might have realized that I made a mistake by putting a light coat of dielectric grease on the wheel speed sensors. Are they supposed to be completely clean when installed? I cleaned a fair bit of tan grease off a couple of them but didn’t drive the truck after to see if it fixed anything.

 

I'm 99% sure these should be installed dry. I'd clean it thoroughly and see what the truck says. You may need to disconnect the battery to reset everything.

 

So this afternoon I moved onto the windshield washer problem until I have a chance to get a good scan tool hooked up for the 4wd issue.

The washer fluid reservoir was all gummed up inside with old fluid so I pulled it, cleaned all the filters, and blew out the lines. Now I can get rear washer fluid to run, but not the windshield. When I hit the windshield washer switch I hear the slightest click by the reservoir but the motor doesn’t run. Do you think the valve controlling the windshield line might be frozen up and not opening? I cleaned the terminals but still no luck.

I’m afraid this truck is going to test my patience. All of these ‘easy’ fixes that I bought the rig expecting are turning out to be some interesting troubleshooting. Good for testing my wrenching skills I suppose.

 

Sounds like the pumps dead, it should make noise when sprayed. I assume the rear pump makes a noise when you spray?

Cheap route would be to put some -20 washer fluid and see if it clears up if it’s frozen. But sounds like the pump to me. Good luck

 

Damn, I feel dumb now. I was thinking the big pump (that I now realize is for the headlight cleaning) was the only pump and the other connections were just valves to open or close each line. Now I realize they are all pumps for each function. The windshield connector has power so it is most certainly a bad windshield pump.

I really feel like I’m on a roll now for catching my mistakes. I just went back under the car to check the signal to the transfer case and realized that I had my voltmeter on AC yesterday and that explained the inconsistent signal. So, now that I’m on DC both the upper and lower plugs have 12v on the center 4 wires each. I moved up to the ADD and the plug doesn’t have any power going to it at all. That might be normal because from what I understand the computer needs to register the transfer case has moved to 4hi before activating the front axle lock. I’m wondering if my transfer case is stuck somewhere between 2hi and 4hi which is why the 4hi light is the only light flashing?

 

If the light is flashing, it definitely means it's not totally engaged. I'm kind of surprised you don't have a beeping alarm. Is there a chance the previous owners found the beeper speaker and disconnected it?

 

I

I doubt the owner did that but maybe his shop did. He was pretty well off though and bet if he brought it to a shop he would not have have had any problem paying for the repair. I think he just didn’t want to deal with it and got a new car instead.

So if you think the transfer case is between shifts I should be able to completely remove the shift actuator and manually move the shift forks to see if the light shuts off, correct? Last night I left the battery unplugged and this morning when I turned the ignition on (before I even started the motor) the 4hi light was already flashing.

 

Here’s a quick update for anyone who is interested. I read some threads where people disconnected the 4wd module for a few minutes to reset the system. Unfortunately that didn’t work for me.

I decided to pull the 4hi actuator back off and test the actuator with it plugged in to the vehicle but not mounted on the actuator housing. When I moved the 4hi switch in the cab nothing moved on the actuator itself. I tried multiple combinations of 2hi and 4hi with the ignition on and off between shifts and still no movement from the actuator.

I tried to manually jump power to the actuator from the battery and the only two pins that produced movement were the two on the far right. I plan to add grease again once I get it working properly.

All this leads me to believe something is wrong further up the system. Either a bad 4wd module, relay, or 4wd switch. Does everyone’s 4wd switch in the cab make a sound when it is activated? Mine is completely silent and I’ve read some people mention there is a slight noise that comes from the switch.

 

Interested....I have an inconsistent problem where my truck won't engage 4hi. The relays behind the dash will click, but nothing happens under the truck. Then the 4Hi light will flash quickly. Sometimes the VSC light comes on when it messes up, sometimes it doesn't. Sometimes the system works flawlessly, sometimes it doesn't. There seems to be no consistency with the issue I'm having.

 

My 4Hi is flashing, traction control light is solid, and you can hear an audible beep. What do you think the issue is?

 

Sorry I haven’t gotten back on here to give any updates. Unfortunately after much frustration and trips to the dealer and our local “Toyota Specialists” we have not been able to get 4WD to engage.

First I took the truck to the “Toyota specialists” who told me they were willing to work on the transfer case actuator without splitting the transfer case. They thought the problem was the ADD so I paid for them to replace that and it didn’t solve the issue. They then recommended replacing the transfer case actuator and told me they needed to split the case to do so.

Next I took it to our Toyota dealer to get a second opinion and they found that a wire to the ADD had rodent damage. When the wire was fixed the flashing 4HI light turned off and cruise control worked but 4wd would still not engage and it would flash 4hi when you attempt to shift it. They said there was an issue with the ADD so I decided to take it back to the “Toyota specialists” to check their work.

When I took car back to the “Toyota specialists” and they believed the 4WD module to be bad and the ADD to be fine. They replaced the module and still 4wd wouldn’t work. They then diagnosed the case actuator is out of time from previous repair attempts I had made on the truck. I then paid them more to attempt to retime the transfer case actuator even though I was certain it was back to the factory location. Finally, they want to replace the actuator by dropping the transfer case which went against what they told me when I first dropped the truck off at their shop.

Basically, I feel like a dumbass for diving into the transfer case actuator myself when the problem was only the rodent damage on the wires going to the ADD. And feel even more like a dumbass for continuing to trust the “Toyota specialists” to continue to do work on the truck after they improperly diagnosed the problem from the start.

So, now I’m planning to cut my losses and sell the truck at 2wd value. The transfer case makes noise and turns the front driveline but never completely engages 4hi. The only thing left I can think of is maybe the micro-switch on the transfer case shifter is screwed up and not making a connection. Does anyone know a way to source one of these without buying the entire actuator?

 

My guess is lack of use.

 

Not true in my case, but I don’t know about OP

 

Hate to revive an old thread but this is exactly what my 2008 Tundra is doing…ever fix it OP or did you sell?

 

Do you have any codes? More specifically C codes? You can try a zero point calibration, I don't have 4wd, but when I had traction, lsd lights flash and another light flash, maybe the ABS light, I lost ABS. An assumption something is interrupting the signal, or check fuses.

 

Check for codes that don't light the MIL. C1340 is pretty common "center differential lock" which really means ADD error. I replaced my ADD actuator and have traced it back to the 4wd switch not engaging in my transfer case actuator.

More to come next week after I tear into it, again...