No speedometer or odometer( first gen)

I dont get any speedometer or odemter and no VSS reading from my obd2 scanner... I know the sensor is good and has connection to the ECM I figured it was the ECM but the on a put in didn change it at all. Also could this make my AC not run? chatgpt said something about it but no idea if thats accurate.

 

1) Never trust AI for car diagnostics.
2) Nobody on this forum is going to be able to help you if you can't GO HERE, scroll to the "Vehicle One-Line Description" field, and tell us your truck (1) YEAR, (2) CAB TYPE, (3) Engine type, (4) drivetrain type 2WD/4WD, then click the [SAVE] button.

If you want help, please, do #2. Help us help you.

Only the 2005-2006 trucks use the rear ABS sensors to gauge speed. So if you have a 2000-2004 truck, you're barking up the wrong tree by looking at ABS. This is the exact kind of misinformation AI will give you.

 

alright sorry about that i filled it out but its a 2001 tundra limited acess cab and I defiently need to be less dependent on AI its screwed me over many times

 

Speed sensor for a 2001 is on the driver side of the transmission just above the sway bar. Check also that the wiring harness is not damaged.

 

Don't trust AI for anything with your vehicles.

Can you add V6 or V8, 2wd or 4wd? I think our gen get the speed off the transmission, but not positive. If you can crawl under the truck and look for anything loose or worn around the transmission, that would be a good starting point. Speed sensor shouldn't have anything to do with the engine being able to start and idle.

 

No, but the neutral position safety switch on the side of the transmission would. If the transmission can't tell which gear it's in, or thinks it's in any gear other than park or neutral, it won't let you start the truck. Which is why loose/damaged wiring on the trans, looking for melted connectors, etc. would be a good move. You and @bfunke are on-point.

 

Always wondered why our trucks don't have a bypass for that like all the Tacomas I've owned.

 

NO my truck runs and my VSS sensor is on my transfer case on the driver side i know the sensor is good and the ECM is good becasue i tried it with another one and the same thing happened...

 

Do you know for a fact the harness is good? Pop it off, inspect for melting, corrosion, clear signs of shorting, loose pins, etc?

 

The other possibility is, quite simply, you have a bad gauge cluster. But if you’re saying an OBD scanner isn’t showing anything either, then it’s probably not the case.

I haven’t looked at the FSM for your year lately to see if there are steps to troubleshooting the issue, but I bet if you download the EWD, it’ll help you trace back thru the wires from the sensor backward to see what may be disconnected, or chewed. I wouldn’t be the least bit surprised if you found an upstream connector disconnected, but I’m also surprised there are no pending or set codes. There are no codes, right?

 

I didn’t see any loose connections or melted wires. One thing I did see was a retraced wire in the back of the gauge cluster, but I reconnected it and nothing happened. I’ll put a picture of it. I do get the code vehicle speed sensor circuit and then I was trying to figure out what Pen it is on the ECU so I could make sure I was getting signal and then make sure I was getting a signal.
the yellow wire alone you see in the back is the one connected ot where this yellow and blue one should be

 

Ive been doing some research and just realized these thing have two VSS one that has a plastic gear and the other that has a a magnetic setup so that helped me figure out my next steps also is it normal for gear oil to come out when I remove this VSS (the one with the gear)? now ive learned my lesson AI sucks at cars and me but now know how to fix it

 

I can't stress to you enough.

Hit the community info thread: https://www.tundras.com/threads/so-you-wanna-buy-just-bought-a-1st-gen-tundra-eh.115928/

Go to the 6th line of text on the thread. Look for the phrase "Service manuals". Click the link. Download the manual to your device by clicking the down-arrow/download button in your device.

Yes. It's for 2003, so there will be very slight differences. But generally speaking, that manual will unlock a wild amount of diagnostics that are applicable across all 2000-2004 Tundras.

 

Okay sorry about that but I got to exited and spoke to soon on the VSS... its actually good and this is what it looks like almost looks like some kind of a bypass the each yellow wire wraps around one of them and one runs up to the gauge cluster and the other to no where it was just tucked underneath the carpet of the floorboard I couldn’t see any other surrounding wires

 

Random shot in the dark here, but is your truck lifted? It looks like someone may have tried to do a yellow box, or some other kind of speedo adjustment.

https://www.tundras.com/threads/yellow-box-speedo-calibrator.31996/

 

It’s lifted a little but the wiring on mine looks put together and doesn’t go near a yellow box I recently tore my dash apart and I didn’t see it so i figured mine is some sort of bypass but idk what exactly

 

I would peel back that wire loom and see what sort of Mickey Mouse wiring PO did there.

 

This is what I’m working with

 

Ok, now where do the yellow wires go?

 

the one on the yellow and blue wires runs to gauge cluster where the yellow and blue wire should go and the other one i found underneath my carpet of the driver side not connected to anythoing

 

The 2004 AC truck’s (in both 2wd and 4wd configuration) speedometer gauge also gets its speed signal from the rear ABS sensors…well to be more accurate, the signal comes from the rear ABS sensors to the ABS pump assembly, then up to the instrument gauge.

 

Now measure continuity in the blue/ yellow and pink/blue wires.

 

They clearly had it attached jury rigged to something, for some reason. Do your best to reverse it - remove the yellow wires, and completely coat those stripped sections with something protective (like GB brand liquid tape) so they don't touch each other, then repair the blue/yellow wire at the gauge cluster.

I'd need to dig up the 2001 EWD to figure out what those two wires are. If I had to guess, the above comment about adjusting the speedo signal output (like what a YellowBox does) due to running oversized tires.

 

I got everything back to how its supposed to be and i got nothing

 

The Pink/Blue conductor the yellow wire underneath carpet is connected to is the GND for the VSS.

A VSS needs a GND, 12vdc and a Signal wire which goes to Combination Meter which is used for Speedometer and Odometer. The Speed and TACH/RPM signals then exit the Combination Meter to the ECU.

I've had crow before but Odometer reading does not go to ECU, which is a reason why your scan tool doesn't see it.



I would clean up that mess as others suggested, then do what's needed to put Pink-Blue and Blue-Yel that goes from VSS to Combination Meter back together. At least your Instrument Gauge would then have Odometer and Speed Odometer

 

They maybe had the damn wires attached to an aftermarket speedo gauge, honestly. It’s possible the cluster wasn’t working and that was the PO’s solution. “Cheaper to buy a cheap external gauge on scAmazon than to replace the cluster!”

 

Its fixed I just re did the bypass because im not trying to find the reason they did it in the first place but thank yall