Multi-Function Switch Malfunction?? Blinker & RPM's

[JWaldz]

So lately I've having this weird issue where when I use my blinker at speeds above 40-ish and in final gear my rpm's will drop and steadily bounce around, like a hesitation feeling.

It's kind of hard to explain. It feels like the torque converter is unlocking but can't figure out what gear it wants to be in. If I give it any gas it will kick into lower gear and stops doing it but if I let off it acts like it shifts but not completely and starts bouncing the rpm's around again.

Otherwise, the vehicle drives and shifts fine in normal operation. It's only the blinker (both positions) that causes the problem. I've tried using other combinations of switches to see if it was a parasitic electrical draw but nothing else effects driving like when using the blinker and only at higher speeds in last gear.

The multi-function switch itself seems to operate correctly as well. Blinkers, headlights, high-beam, and fog light functions all work properly.

I don't know what else to do other than replacing the multi-function switch to see if it fixes the issue. If it doesn't, I have no clue where to start.

I'll try to post a video later to show what's going on.

(specs: 1999 limited automatic 200k)

 

[vwtech]

Can you get your hands on a wiring diagram for you truck? If so I would start looking for circuits from multi-function switch that connect to, or share fuses, grounds, relays that the ecm or tcm uses for signal input. Or could be something like two wires have chaffed together, and when you activate the turn signal circuit it pisses off an input to something your power train needs. These problems are tough to track to down in the garage.

 

[Tucson4runner]

I'm having the exact same issue with my 2000 limited. I think I've narrowed it down to my led cluster swap. I changed out the battery warning light with an led only to find out that that light is part of the charging system and that now it's on because it's reading a fault in the line. That's when this problem started for me. All of my blinkers are leds so I thought first it was the blinker relay but I replaced that and it didn't help. I threw away my original bulbs so I'm currently trying to track one down and maybe that will fix the issues.

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[JWaldz]

I'm having the exact same issue with my 2000 limited. I think I've narrowed it down to my led cluster swap. I changed out the battery warning light with an led only to find out that that light is part of the charging system and that now it's on because it's reading a fault in the line. That's when this problem started for me. All of my blinkers are leds so I thought first it was the blinker relay but I replaced that and it didn't help. I threw away my original bulbs so I'm currently trying to track one down and maybe that will fix the issues.

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I don't know EXACTLY when this started but I know for sure that I've had my led cluster and led blinker lights far before this issue arose. Still doesn't explain why the blinker is the only thing that causes it??

 

[JWaldz]

Can you get your hands on a wiring diagram for you truck? If so I would start looking for circuits from multi-function switch that connect to, or share fuses, grounds, relays that the ecm or tcm uses for signal input. Or could be something like two wires have chaffed together, and when you activate the turn signal circuit it pisses off an input to something your power train needs. These problems are tough to track to down in the garage.

It would be a good start. I'll see if I can get one. If it's a bad ground and NOT the m-f switch it could take time to find :mmph:

 

[Tucson4runner]

I don't know EXACTLY when this started but I know for sure that I've had my led cluster and led blinker lights far before this issue arose. Still doesn't explain why the blinker is the only thing that causes it??

I am assuming that's when my problem started but I'm also not 100% sure that's when it started either. I agree it doesn't explain why the blinkers are the only thing affected but after testing and checking and changing wires and lights and plugs it's the only thing I feel I haven't tried yet. I'm in over my head trying to identify this.

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[JWaldz]

I am assuming that's when my problem started but I'm also not 100% sure that's when it started either. I agree it doesn't explain why the blinkers are the only thing affected but after testing and checking and changing wires and lights and plugs it's the only thing I feel I haven't tried yet. I'm in over my head trying to identify this.

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I'm replacing the m-f switch soon once the guy pulls it and sends it to me. Hopefully it's a bad ground in the switch.

 

[jgue467]

So lately I've having this weird issue where when I use my blinker at speeds above 40-ish and in final gear my rpm's will drop and steadily bounce around, like a hesitation feeling. ....

Yeah could be a bad ground and/or crossing ground. The Durk tuned me into this when I posted about my crazy issue. My 01 while using the cruise works fine until I decide to change lanes and use guess what? My blinkers will cause the cruise to disengage and a very slight, almost imperceptible stumble while operating the blinkers. The Durk thinks a crossing ground between the blinkers and the brake lights sends a signal to the ECU telling it I'm braking so disconnect the cruise. So I plan to change out the brake leds to regular bulbs to see what happens. You may want to test what signals are sent on the old unit. Luck. :cowboy:

 

[Tucson4runner]

Yeah could be a bad ground and/or crossing ground. The Durk tuned me into this when I posted about my crazy issue. My 01 while using the cruise works fine until I decide to change lanes and use guess what? My blinkers will cause the cruise to disengage and a very slight, almost imperceptible stumble while operating the blinkers. The Durk thinks a crossing ground between the blinkers and the brake lights sends a signal to the ECU telling it I'm braking so disconnect the cruise. So I plan to change out the brake leds to regular bulbs to see what happens. You may want to test what signals are sent on the old unit. Luck. :cowboy:

Yup! This has to be it because this is my other problem. I converted my tails to 01' led tails and within weeks converted the front to led and did the led cluster swap. Man you guys are making my day today. So what can I do to keep my led tails because I no longer have my stock tails and the leds are built into these I can't swap bulbs out. Can I just add a resistor inline?

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[JWaldz]

Yeah could be a bad ground and/or crossing ground. The Durk tuned me into this when I posted about my crazy issue. My 01 while using the cruise works fine until I decide to change lanes and use guess what? My blinkers will cause the cruise to disengage and a very slight, almost imperceptible stumble while operating the blinkers.

I didn't think of trying the cruise control and the blinkers.. I'll see what it does on my way home tonight.

 

[JWaldz]

[MENTION=75316]jgue467[/MENTION]

Sure enough, put the cruise on and tried the blinker. It kicked it out of cc.

 

[JWaldz]

I don't know why this problem just started out of the blue now.. I've had led tails and gauges for some time now. I don't have led blinkers though.

 

[TheDurk]

So lately I've having this weird issue where when I use my blinker at speeds above 40-ish and in final gear my rpm's will drop and steadily bounce around, like a hesitation feeling.

It's kind of hard to explain. It feels like the torque converter is unlocking but can't figure out what gear it wants to be in. If I give it any gas it will kick into lower gear and stops doing it but if I let off it acts like it shifts but not completely and starts bouncing the rpm's around again.

Otherwise, the vehicle drives and shifts fine in normal operation. It's only the blinker (both positions) that causes the problem. I've tried using other combinations of switches to see if it was a parasitic electrical draw but nothing else effects driving like when using the blinker and only at higher speeds in last gear.

The multi-function switch itself seems to operate correctly as well. Blinkers, headlights, high-beam, and fog light functions all work properly.

I don't know what else to do other than replacing the multi-function switch to see if it fixes the issue. If it doesn't, I have no clue where to start.

I'll try to post a video later to show what's going on.

(specs: 1999 limited automatic 200k)

Let's see if I can help. Try this: Hit your hazards as you're driving along and see if it has the same effect. It's a slightly different circuit so it may give me a clue. If hazards do the same thing, I really doubt changing the stalk switch will do anything as the stalk is not involved in that circuit routing.

I have a '99 truck and a paper '99 EWD so I have the diagrams available.

EDIT: I'm working on a theory here. The Cruise Control and the blinker both ground through the Center J/B. Has there been any under dash electrical work, like a stereo installation, that would mesh with the onset of this problem? Any water leaks in the front of the cab?

 

[JWaldz]

Let's see if I can help. Try this: Hit your hazards as you're driving along and see if it has the same effect. It's a slightly different circuit so it may give me a clue. If hazards do the same thing, I really doubt changing the stalk switch will do anything as the stalk is not involved in that circuit routing.

I have a '99 truck and a paper '99 EWD so I have the diagrams available.

EDIT: I'm working on a theory here. The Cruise Control and the blinker both ground through the Center J/B. Has there been any under dash electrical work, like a stereo installation, that would mesh with the onset of this problem? Any water leaks in the front of the cab?

I have tried the hazards before, and it does the same thing.. No recent electrical jobs that could relate and no leaks into the cab that I know of. I wish I could remember when this started so I could pin-point it to some kind of modification.

Here's a list of jobs I've done within the past 6 months.. Just maybe if we can find some similarities to others and track down a cause.

-Front Tundra Brake Upgrade (refresh, already had them just got new parts)
-Rear Axle Swap (Diamond axle, resulted in loss of ABS and ebrake)
-Redid valve cover gaskets, they were leaking
-Moved my fuseblock to a new location under the hood and added an in-line breaker. No new accessories added though.
-Replaced all 4 shifter bushings.
-New steering rack


That's all I can think of right now and I believe covers the past 6 months. I know this issue hasn't been going on for that long. I want to say I just started noticing it maybe towards the beginning of February. I don't have LED turn signals (front or rear) but I do have LED Tail Lights.

 

[Tucson4runner]

Me having the same issue have done this in the past 6 months.

Added led tail lights
Added led bar using reverse light as trigger
Led cluster swap
Led front blinkers
Led blinker relay
Replaced battery
Hid headlights
Hid fog lights
2 sets of ditch lights
2 led bars off left and right of roof rack with back lights wired into corner lights
Replaced amp for sub

During this is when I noticed the cruise control issue and after that I was driving with the buzzing blinkers for about a month before I put the new relay in.

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[JWaldz]

[MENTION=10169]TheDurk[/MENTION]

Could a sound/stereo system be a cause? I mean, I haven't changed anything in my system but I do have an amp and 2 subs. I have a buddy that also has a sound system and his vehicle has been doing this for as long as he can remember. Since Tucson4runner mentioned replacing an amp it brought it to my attention.

 

[Tucson4runner]

[MENTION=10169]TheDurk[/MENTION]

Could a sound/stereo system be a cause? I mean, I haven't changed anything in my system but I do have an amp and 2 subs. I have a buddy that also has a sound system and his vehicle has been doing this for as long as he can remember. Since Tucson4runner mentioned replacing an amp it brought it to my attention.

Come to think of it, my deck is a flip out pioneer dvd player that I've owned for about 7 years... Recently it will shut off temporarily and turn back on. There is no rhyme or reason that I can see as to when it does it. Seems random, could happen every 2 minutes or not all day. I assumed it was the age of the deck but not it could be something more. I'll try and get in there this weekend and see if I find anything.

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[TheDurk]

[MENTION=10169]TheDurk[/MENTION]

Could a sound/stereo system be a cause? I mean, I haven't changed anything in my system but I do have an amp and 2 subs. I have a buddy that also has a sound system and his vehicle has been doing this for as long as he can remember. Since Tucson4runner mentioned replacing an amp it brought it to my attention.

Well, one of Durk's (aka ElDurko) rules is that, after grounds, weird electrical issues are likely related to voltage issues. So, if something is wired in a strange fashion, and that plus the blnker load, could trigger something.

Anyway, I strongly doubt the stalk switch will be your issue if hazards do the same thing, as the hazard switch takes it completely out of the system.

Let me study some, I'll get back to you.

 

[Tucson4runner]

[MENTION=10169]TheDurk[/MENTION] is sounds like something is failing due to inconsistent mods done by all of us. Could you give me further guidance on where my ground are located and I will start with checking each of those. Or guide me to a spot in the FSM and I can locate them in there. Thanks!

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[TheDurk]

[MENTION=10169]TheDurk[/MENTION] is sounds like something is failing due to inconsistent mods done by all of us. Could you give me further guidance on where my ground are located and I will start with checking each of those. Or guide me to a spot in the FSM and I can locate them in there. Thanks!

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The key ground for this is the IE ground under the dash on driver's side way over on the left and high up and its mate IF on the right side. I've actually never seen them. I don't know what you have to do to get to them. IE might be visible if you remove the cluster, I don't know. It could also be that whoever installed these aftermarket mods tapped into the white-black wire from one of those ground points and compromised it. Easy to do with those (*&^%$^^&& blue tap thingys. Those ground points feeds 101 things on the truck, and the wires from it are not very heavy. So, while people are pretty good about providing adequate fused power to a mod, sometimes they can overload a factory ground wire, not thinking about all the current it has to carry. It's always better to ground a mod of any size directly to the body or chassis.

It's hard for me to troubleshoot over the internet, because I don't know what was done. Factory stuff I can look at a book. So all I can say is look for anything funky in terms of non-factory wiring, junctions, etc., especially involving white-black wires and blue add-on tap thingys. Also, sometimes small windshield leaks can compromise that ground point, even though you don't see anything in the cab.

I think you both should run voltage tests with the engine running and see if you get 13.5-14.5 Volts. A weak charging system will not do this any good. Then see if there is a wide swing in volts with the blinker engaged. If there is, I'll run the same test on mine as a control and we can compare.

I don't think we have to worry about voltage at any point other than just at the battery, because the TURN and HAZARD operations use separate power feeds from separate fuses. They DO, however, use the same ground.