domitus

I posted a few times about some problems I am having with my electric speedometer on the 92 3.0 m/t (jumps to 45 and stays there), but couldn't decide if it was the sensor itself or the cluster. Well, the other day I was driving around going about 25, and it jumps to 45 as usual, and I get pissed off and smack the dash and... it started working again. The next few days same situation, speedo jumps to 45, smack the dash, speedo works. Previous posts say that the speedo itself is about $400 at dealership, and unfortunatly I think that is what my problem has been narrowed down to.

Before I buy a new or used cluster for a switch, like bustah49's thread, has anyone had a similar cluster problem that was fixable by getting in there and tightening, lubing, spraying, repositioning, anything, etc? I am afraid to take the cluster out yet (as per the cool indiglo gauges write-up) unless I know I can even do anything to it. If someone could tell me if this "fix" is even possible it would be greatly appreciated. Thanks.

domitus

So no one, in the process of replacing of a cluster, has ever felt the urge to look inside and see what was up and how it worked? I am not talking about a fix like lubing the cable, I have an electric. More like maybe something inside is loose enough or not connected or whatever to the point where when I punch the dash the speedo starts working? Just need a heads up before I go inside.

trythis

It could be, if this is how they are made, that the gear in the tranny casse that sends speed pulses to the speedometer is stripped and locking up funny, or maybe a short somewhere else. I have no idea if they are made that way.
You can get a cluster off ebay for loads chaeper than new. Mine is cable driven, so I can't help you. If you had a cable driven, your dash would sound like overloaded 18wheeler tires rumbling down the highway, so there is that to help you feel more fortunate!

wrenchmonster

There are a number of people involved in "instrument service". All they do is testing and recalibrating of clusters and gauges and all sorts of other stuff. Usually you mail off your cluster and get it back in a few days along with a report. This can still cost several hundred dollars so be sure to get a quote before sending it out. Any local dealer can probably refer you to a service.

Of course diagnose the problem to make absolutely sure it is the cluster at fault. Sometimes it's simply a loose connection or sender and you get lucky. If you determine it is indeed the cluster you're better off getting a new one or having it repaired. It's a specialty and you'll need the right tools and knowledge to fix the cluster properly.

miket223

Just buy a new or used unit. Those speedo heads are not serviceable except by a specialized shop if you want your odometer to read a certain value, as opposed to "000000".

Information on diagnosing the annoying electronic speedo problems is sketchy. From my experience, it seems to be about 60/40. As in, it is either the speed sensor (60%) on the t-case or the speedo head (40%).

domitus

Cool, that covers all I needed to know
Figured it was worth a shot. I like taking things apart, but have little experience with printed circuit boards and electrical stuff in general, so a specialized job is a bit out of reach.

Shouldn't the fact that I hit the dash and it works point to me being in the 40% with cluster issues?

I keep thinking about that Indiglo Gauge mod or a custom gauge and might just take the dash off and all that to see whats up, the clock keeps wiggin out too.
Thanks.

miket223

I would have to agree with you. If that vehicle was in my shop, I would replace the speedo head if it started working after a quick beating. Unfortunately the speedo/odometers are only sold by Toyota as a complete assembly and your truck will be at 000000 miles unless you pay to get it set to your old odometer reading which can cost as much as the speedo head itself. The speedo head is $290 from Toyota I think.

wrenchmonster

I totally disagree with this statement. It is exactly this type of "diagnosis" that causes the public to view repair technicians in a poor light. To say that the cluster is at fault just because you hit the dash and it corrects itself is simply wrong. Although it could very well be the cluster, it could also very well be a loose connection, a corroded connection, a broken wire inside its insulation, a power or ground issue, etc.

The point is, without doing a solid diagnosis you're just guessing. If you don't know that the cluster is at fault 100%, then you could end up replacing the cluster and have no correction of your problem. I'd strongly suggest doing some real diagnosis before throwing parts at the problem. I guess it boils down to whether you want to be a technician, or just a parts replacer.

By the way, just so you are aware, it is illegal to change an odometer reading without notifying the DMV.

miket223

You can disagree all you want, I'm still right. I've dealt with no less than 25 of these electronic speedo failures from that generation vehicle and there is no useful diagnostic information provided by Toyota. The diagnostic information in the FSM consists of the following: "If speedometer is not functioning, then fix it."

The original description of the problem also indicates that the speedometer will stick at 45 mph despite the vehicle's actual speed. This behavior is not conducive of a failure in the speedometer sensor or any wiring issues. Based on my experience and the guy's description of the speedometer problem, I can already tell you that the speedometer assembly needs replacement. Or, maybe if this were your customer you should get about 2.0 hours of diagnostic / R&R time out of him first for a problem that can be fixed blind folded.

wrenchmonster

Although I don't have a FSM in front of me, I sincerely doubt is states "If a speedometer is not functioning, then fix it."

I don't know your experience level or skill. Frankly, that is not the issue at hand. My point was not to miss anything simple before just slamming in a new cluster.

I take offense to your statement about my ethics. You do not know me, Sir, and you have absolutely no right to imply that I cheat my customers. There is no need to bash me for stating my opinion.

miket223

Sorry, I meant no offense. I didn't say you cheated your customers, where did that come from?? My remark about the 2.0 hours diag time was in reference to trying to solve a common problem with known common solutions; but, wasting time on unnecessary diagnosis when it is neither required or possible with the worthless information in the FSM. Believe me, I wish Toyota provided sensor output specifications and resistance values for the speed sensor on the t-case. At least then you would know if one of the components was good and could stop gambling with customer money. See this link and go to page 5 for the information Toyota provides. http://personal.utulsa.edu/~nathan-b.../6combinat.pdf. I assure you, there is no other information available except a wiring diagram which is generally useless since you don't know what to probe for on your DVOM. I'd like to add that the "diagnostic" load of bull that is on that page is not reliable. I blew my stack on the first 5 or so thinking I was going to get it knocked out dead cold only to find that it could be either the sensor or the speedo head despite the diagnostic information. Again, sorry for offending you.

zombi

What year is your rig? is it a 4runner or PU?
I have access to about 7 4runners and 2-3 PUs for parts and may be able to get you the cluster you need. I am having the same issue, but my speedo does not work at all.
Also after installing a CD player with a wiring harness, my dash lights quit working.
So I am pulling my dash apart on a regular basis. I am going to replace my cluster and see if that solves anything. I'll be sure to let you know the price of the cluster and if it fixes my speedo.

wrenchmonster

Miket223. No offense taken. I'm sorry too if you took any offense to anything that I wrote. I admit I let my blood boil a little bit, and I shouldn't have let the situation get to me that much.

I'm just tired of the parts replacers. It seems a lot of the "technicians" coming into the field are just that. I've seen mis-diag after mis-diag all the while the tech just passes on the bill to the customer. I've read many posts on this forum where people are chasing their tails trying to fix a problem by parts replacement rather than solid diagnosis. I always try to encourage diagnosis, because that is truly where the skill of a technician lies. Any monkey can bolt and unbolt parts, and I think we can both agree on that.

My ultimate goal was to inspire Domitus to learn a little something about diagnosis. Sorry for hi-jacking the thread, but I thought Miket223 deserved the apology. I'd buy you a beer if I could, but I'll just drink one for you instead.

domitus

miket223 and wrenchmonster- thanks again for the advice, lets hope it's something simple that a little inside inspection can determine. The next issue is finding the time to look inside, we'll see how that goes. Wish me luck, I'll drink TWO beers for BOTH of you and three for zombi, it's a 4runner.