MasonFX

Hello all, first time caller here. I'm a teacher so be gentle with my mechanic's skills.
I just bought today a 98 ES 300, and she's a peach. The only issue is that the ABS light is on the dash, and the speedometer doesn't work. Stuck at 0. I cleared the codes with my home obdii in the hopes... but no dice. ABS light still on, speedo doesn't work.
I took a chance (it was not a lot of money) that I could fix it. I've done my share of reading around on the internet and came here a few times - the answer ranging from sensors under the airbox, to the rear of the transmission (external), replace the cluster, fuse in the wrong area, and the abs sensor getting wonky info from the rear tire.

So, a peach with some issues. But I have faith.

I was hoping someone could tell me if they've come across a fix for the abs issue, including replacing the passenger rear wheel speed sensor if necessary. If a sensor either under the gear box or @ the transmission, let me say the transmission shifts smooth as smooth gets so not sure about those sensors being the issue (have some unwanted experience there from a previously owned 2004 Jetta and the dreaded automatic transmission it held)

Is there a corrolation between the abs issue and the speedo? is it two separate issues?
Any help here greatly appreciated. Thanks.

LeX2K

You could have two problems I would replace the ABS sensor and go from there.

MasonFX

thanks for the reply. The ABS sensor at the passenger rear wheel, yes?

Also I was told by a guy I know down the street to "just get the ABS scanned and cleared, if you've already checked for continuity then it 's probably just a stored code. No, your obdii reader won't clear/reset the ABS"

The ABS sensor check and replace is where I'll start. I'm glad you didn't say the VSS sensor at the trans.

LeX2K

Depends on the scan tool a cheapo one probably won't be able to clear any codes but that doesn't matter when the bad sensor is fixed the code will go away automatically. You can check the sensor yourself with a test meter look for about 1000ohms, more or less I don't know the exact spec usually the sensors fail to an open circuit. The speedo problem could be a bad transmission speed sensor or bad cluster, the latter seems to be more common. You didn't say what the code was but it will tell you location. The rear ones are easy to replace the front can be a pain, some will disagree but I buy the cheapest sensors made never had a problem it's a coil of wire hard to get that wrong.

MasonFX

Ah right forgot to do that, cardinal sin when asking for help! It's the p0500 code
Thanks for your help Lexus2000

MasonFX

Ok update. I replaced each of the ABS sensors and the ABS dash light went away. Success and progress!
However, upon driving for about a minute the CEL comes back on and the speedo still doesn't work. This was last week.

Today arrived my new vehicle speed sensor which per the manual linked in another thread I ordered. It's the sensor that rests on the rear-top of the transmission held by one 10mm bolt. Was actually quite simple. I did it while the battery was unconnected, and when finished I hooked her back up again and within about 3 seconds the cel came back on, still no speedo work.

I'm still confused about which sensors people are talking about when they say VSS. The two under the battery exist in my car. When looking down on them, we'll call them left and right. If one of these are the sensor(s) I should actually be paying attention to, which of those two should be changing out? Anyone feel free to chime in!

edit: turtlepeas has a thread where he's at the point now where he's going to swap out the instrument cluster. He's been at it longer than I have and he's already swapped out the two sensors under the battery, which didn't work for him.
thankfully none of this is hard, just eating up time.

Any help appreciated guys.
John

FromFL

Did you use OEM ABS sensors? On my Nissan, aftermarket ones didn't work and caused my speedo to underreport the speed...had no choice but go with OEM.

LeX2K

Should be able to see the VSS signal on your OBD scanner as you drive. Generic ABS sensors are fine on these cars in my experience, again should be able to see that signal on your scanner depending on how good it is.

MasonFX

Good question, so let's revisit the sequence of events. Each stage involves disconnecting the battery, test driving the vehicle with an obdii reader after parking. It would look like:
stage one = car purchased, inexpensive, speedometer not working, CEL and ABS lights are on. At the time of purchase, every sensor we're talking about is original part on the vehicle.
stage two = replaced abs sensors at the tires, as I read those could trip the speedometer. again, those were original abs sensors - one of which was torn and the sensor was not present at all. His response "it must have fallen out" no reason to even talk about that. I put in a new sensor along with replacing the other ones, and the ABS light is off. Seconds after I notice the abs light is off, the cel comes back on and of course the speedometer still doesn't work.
Stage three = quick one, and the latest one. simply removed the existing sensor and put a new one in. cel comes back on and speedo doesn't work.
I have another oem instrument cluster, and I'm going to try that tomorrow just because it's easy and I have it already. Going to rule out that sensor for now.
Stage four = success. Replaced oem instrument cluster with another of the same year and it turns out within 5000 miles of the one replaced. Upon startup i saw immediately mileage was showing, and when driving the speedo accurately reflected the speed. Interestingly, the gas gauge came off empty to show about a quarter tank, so I will fill and do trip test to see if the new reading is correct or i'm actually flatlining as the original showed.

SUCCESS!!

To reiterate my need, as I see it, I need to know of the two sensors underneath the battery best falls in line with "vehicle speed sensor p0500" code.
there are two, let's call them left and right. I went to a salvage yard three days ago and attempted to take out the right sensor of those two. easy enough to unbolt, but the wires extend far into the housing and it doesn't look like what I've seen when searching for a sensor of this type.
I did not remove the left sensor at the salvage yard, but will try that tomorrow. I'm hoping that's the one, because if it's the right sensor of the two, i'm really missing something.
[edit - no longer required but i'd still like to know just in case something happens in the future. I plan on keeping this car,we've bonded quite nicely. repairs were a cinch.

MasonFX

I have an Actron, lower model but it's been very trusty since I've owned it. Help me understand "see the vss signal" Lexus2000.. while driving, I have it hooked up and look in the active data screen? as opposed to the "read data" and "delete data" screens which is basically what i'm familiar with.
I'll report back with what I find, maybe you or someone can translate that. Probably beyond me at that point if I'm being honest. I'm willing to try.

LeX2K

For clarity the ABS wheel speed sensors are not used as a signal for the cluster, on some cars this is true (they have no speed sensor on the transmission). On your car all the ABS sensors could be bad and the speedo would still work, they are separate systems. I think I posted a link to the service manual that gives the steps diagnose this.

When swapping the cluster do NOT turn the key to ON with it disconnected this will trigger the SRS light and you'll have fun trying to reset it. I don't know where in the scanner it will show real time speed sensor data, or maybe it won't but most have this feature.

LeX2K

I found it
https://www.clublexus.com/forums/es-...l#post10558775
starts on page 105, this is for a 1997 ES so keep that in mind

On the ABS sensors versus VSS to get technical the computer might use a combination of the two for traction control and ABS, but the cluster AFAIK will still work even if the ABS sensors are bad.

MasonFX

Yep cheers for that. The ABS light went off when i replaced the abs sensors so i felt that was solved. I realize I asked that question for clarity to start with so I appreciate you putting the definitive on it.
I will swap the cluster tomorrow.

Still looking for clarity though on the two sensors under the battery people keep referring to as vehicle speed sensors. As mentioned I swapped out the one on the top-rear of the transmission, so the only sensors left that anyone has referred to are the two under the battery. The "right" one when unbolted.. the wires just descend into hell. There isn't a sensor per se to remove and replace that I can see. The "left" one I will mess around with tomorrow at the salvage if I go.

Appreciate the discussion, thanks.

MasonFX

@Lexus2000 the replaced instrument cluster did the trick. I knew I was going to get good news when I turned the car on and the mileage showed (would you believe within 5K miles of the mileage of the one i replaced?) Sure enough speedo worked when driving.
ABS sensors fixing the ABS idiot light was a for sure. VSS at the top-rear of the transmission replaced, but the cel was still on and no speedo.. very likely the original vss works just fine.
all in all an easy resolution for me, crossing fingers it stays.

LeX2K

Excellent. from what I've seen so far this problem has been the cluster every time. Get this, the speedo head is different if you have vehicle skid control (VSC)

83220-33050
83220-33051 W(VSC)

I guess means the ECU relies on the speedometer, or maybe a bad speedo head shorts out the VSS signal. Having the mileage close is a good bit of luck otherwise you'll need to swap the non volatile RAM chip.