rigtec
New member
Hi tech team,
For those of you who have had (or will) experience system warning lights/icons on the Tach-O-Meter side of the instrument cluster, for NO apparent reason e.g., added new upper/lower CA's, a lift, longer coil-over springs, high performance shocks...etc, I'm here to let you know that this trouble is becoming more common exponentially, but not w/o cause.
I've had this happen to me when I first purchased the truck back in 2012. When it happened, I had NO experience with the GEN-5 4Runner or it's sophisticated electronic system(s), so I took it to the dealership where I bought it from. Now when I first got the truck I installed a set of PIAA 520 fog-lights; my very first mod. As soon as I drove it into their check-in bay, they started pointing at the front of the truck so I assumed that there was gonna be some drama.
I went into the service area and told the girl who writes up the service tickets why I was there. She said, "You can have a seat right over there and someone will be with you shortly"! When I spoke to the service rep, he started questioning me about the fogs (before even looking at the reason that I was there); I wasn't too happy after I had just dropped close to Fifty large (in cash) just a few months earlier!
He also said that I needed to remove those fog lights first BEFORE he could look at it! That's when I started getting aggressive cuz he was now pissin' me off!
I said a few things to him (bout his momma) and then walked out; I had been a class A auto tech for many yrs in my earlier days, before I moved into Comm'l/Indus'l HVAC Tech Services, and I NEVER was afraid to look into a customers problem before opening the hood; as a matter of fact, these were the problems I looked forward to!
So now I was looking for a local (non)dealership auto repair shop to help me ring this trouble out. Well, they all pretty much said the very same thing: "Sorry bud, but we don't have the proper equipment to test this new vehicle's electronic systems out at this time"! ...but at least he was being honest about his dilemma! This problem stayed that way for about six months.
I actually purchased a brand new Main body ECU compu network ($600 +); I did know that, that's what controls ALL of the interior ecu's because I bought the GEN-5 4Runner wiring diagrams. But here in NJ, the snow wouldn't give a break so that I could install it. We had about 24 inches of snow on the ground already. Then another foot or so fell on top of that, then another storm came!
Well I never did get a chance to install the new ECU; but that was a good thing cuz I found the real problem! The reason that I'm writing this to you is because there were NO TROUBLE CODES thrown by any of the sensors; where those codes are generated. These warning lights/icons were coming from the ecu's themselves, so there was no communication from the OBDII.
That's when I learned that the 'Main body ECU compu was not being energized; which caused all of those warning lights: Slip, VSC, TRAC, ABS, BRAKE, Steering, security system... this happened again yesterday! Even the Speed-o-meter & Tach-o-meter stopped working intermittently. Ahhh, but I remembered why this happened before (I'll NEVER forget that)!
I just got out of the truck, opened the hood; there's a 10A fuse in the main fuse/Rly box labeled B+ ECU. I removed that and gave a good look to see if it was blown or not... it looked good! Next, I pulled the 'Short-pin' out to de-energize the ecu's just to clear the history log, and returned them both to their slots. All was good... but it started that again today.
So I pulled those two devices (fuse and Short-pin) out again today and returned them to their slots; only to fine those warning lights still on. :noidea: Hmmmm! So I replaced the 10A fuse with one of the spares in the box and the trouble was GONE! Apparently, the fuse has a hair-line crack in it so it's not always feeding the Main body ECU as it should! So... should you run into a similar problem FOR NO APPARENT REASON, pull the B+ ECU fuse out and check it, or just replace it; that just may be the cause!
If it's the MB-ECU compu, I just happen to have a new extra one lol! 'Best to you',
rig, cheers!
For those of you who have had (or will) experience system warning lights/icons on the Tach-O-Meter side of the instrument cluster, for NO apparent reason e.g., added new upper/lower CA's, a lift, longer coil-over springs, high performance shocks...etc, I'm here to let you know that this trouble is becoming more common exponentially, but not w/o cause.
I've had this happen to me when I first purchased the truck back in 2012. When it happened, I had NO experience with the GEN-5 4Runner or it's sophisticated electronic system(s), so I took it to the dealership where I bought it from. Now when I first got the truck I installed a set of PIAA 520 fog-lights; my very first mod. As soon as I drove it into their check-in bay, they started pointing at the front of the truck so I assumed that there was gonna be some drama.
I went into the service area and told the girl who writes up the service tickets why I was there. She said, "You can have a seat right over there and someone will be with you shortly"! When I spoke to the service rep, he started questioning me about the fogs (before even looking at the reason that I was there); I wasn't too happy after I had just dropped close to Fifty large (in cash) just a few months earlier!
He also said that I needed to remove those fog lights first BEFORE he could look at it! That's when I started getting aggressive cuz he was now pissin' me off!
I said a few things to him (bout his momma) and then walked out; I had been a class A auto tech for many yrs in my earlier days, before I moved into Comm'l/Indus'l HVAC Tech Services, and I NEVER was afraid to look into a customers problem before opening the hood; as a matter of fact, these were the problems I looked forward to!So now I was looking for a local (non)dealership auto repair shop to help me ring this trouble out. Well, they all pretty much said the very same thing: "Sorry bud, but we don't have the proper equipment to test this new vehicle's electronic systems out at this time"! ...but at least he was being honest about his dilemma! This problem stayed that way for about six months.
I actually purchased a brand new Main body ECU compu network ($600 +); I did know that, that's what controls ALL of the interior ecu's because I bought the GEN-5 4Runner wiring diagrams. But here in NJ, the snow wouldn't give a break so that I could install it. We had about 24 inches of snow on the ground already. Then another foot or so fell on top of that, then another storm came!
Well I never did get a chance to install the new ECU; but that was a good thing cuz I found the real problem! The reason that I'm writing this to you is because there were NO TROUBLE CODES thrown by any of the sensors; where those codes are generated. These warning lights/icons were coming from the ecu's themselves, so there was no communication from the OBDII.
That's when I learned that the 'Main body ECU compu was not being energized; which caused all of those warning lights: Slip, VSC, TRAC, ABS, BRAKE, Steering, security system... this happened again yesterday! Even the Speed-o-meter & Tach-o-meter stopped working intermittently. Ahhh, but I remembered why this happened before (I'll NEVER forget that)!
I just got out of the truck, opened the hood; there's a 10A fuse in the main fuse/Rly box labeled B+ ECU. I removed that and gave a good look to see if it was blown or not... it looked good! Next, I pulled the 'Short-pin' out to de-energize the ecu's just to clear the history log, and returned them both to their slots. All was good... but it started that again today.
So I pulled those two devices (fuse and Short-pin) out again today and returned them to their slots; only to fine those warning lights still on. :noidea: Hmmmm! So I replaced the 10A fuse with one of the spares in the box and the trouble was GONE! Apparently, the fuse has a hair-line crack in it so it's not always feeding the Main body ECU as it should! So... should you run into a similar problem FOR NO APPARENT REASON, pull the B+ ECU fuse out and check it, or just replace it; that just may be the cause!
If it's the MB-ECU compu, I just happen to have a new extra one lol! 'Best to you',
rig, cheers!
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