How JustAnswer Works:

  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.

Ask Davo Your Own Question

Davo
Davo, Master technician
Category: Car
Satisfied Customers: 3253
Experience:  ASE Master Technician/Advanced Automotive Diagnostic Technician
112340
Type Your Car Question Here...
Davo is online now
A new question is answered every 9 seconds

2000 chevrolet: 5.3L Z71 speedometer..new insrument cluster panel

Customer Question

2000 chevrolet 1500 5.3L Z71 speedometer does not work. A new computer has been installed , a new insrument cluster panel has been installed, and it has been flished. The tech seems to think it is a Class II Serial Data Communications Failure, but does not know what that means.
What does it mean, and how do I fix the speedometer.
the check engine light is on also.
Submitted: 9 years ago.
Category: Car
Expert:  Joe Barcus replied 9 years ago.
did your tech check to see if voltage is at the odo fuse? did he look at the box on the transmission? your check engine light will remain on until its cleared up
Expert:  Marc replied 9 years ago.


Did the tech read the codes and what are they, (the code numbers)
Expert:  Davo replied 9 years ago.
Yes I would like to see code numbers also.
Customer: replied 9 years ago.
Reply to Marc's Post: The code is 608 Output speed sensor circuit fault. A new speed sensor was installed and still didn't work.
Customer: replied 9 years ago.
Reply to Davo/diablo666's Post: code 608 output speed sensor circuit fault. put a new speed control sensor and it still does not work
Customer: replied 9 years ago.
Reply to Joe Barcus's Post: yes voltage checked O.K. code is 608 output speed sensor circuit fault. put a new speed control sensor on and it still doesn't work.
Expert:  Joe Barcus replied 9 years ago.
these kind of problems are hard ones to pin down, if you know for sure the + voltage is there than it must be in the ground. maybe the plug is bad on the sensor??? Im not sure of the voltage that needs to be at that plug one of the other guys should know this in a while.
Customer: replied 9 years ago.
Reply to Joe Barcus's Post: when the new speed sensor was installed the code was cleared and put into gear and the code immediately returned. tried this several times but it still came back and the speedometer still doesn't work.
Expert:  Joe Barcus replied 9 years ago.
I might very well be fishing here and Im sure I am. so If I look like to big of a fool forgive me.
sounds like something in the wiring harness going down to the transmission, un hook batt once more let it clear, and start it again. by what you said it wont show code until you use the shifter. if thats the same way every time then its "could be" two wires touching in the harness going down to the trans. taking the ground away. again this is just guess work.
Expert:  Davo replied 9 years ago.
P0608 is not an output speed sensor code.It is a vehicle speed output circuit code which is a different animal.This code is triggered because an output of the pcm sees a fault not an input as in a speed sensor code would be.There is a dark/green white wire that goes between the pcm and the ipc.It goes to the fuse box along the way and there is at least 1 other dark/green white wire in there.I suggest you get your mechanic to see if the dark/green white wire is open.Just so he doesn't get all confused it is not a class 2 failure those are communication failures and are listed as U1000 series codes.But then maybe his scan tool won't read U codes I don't know.If he has a wiring diagram he can find the wire I would hope.There is also a connector between the pcm and the ipc shown on the wiring diagram.The pin number at the pcm varies according to engine size but the cluster pin number should be A3.Let me know where this gets you.Is your mechanic capable of doing electrical circuit checks?
Customer: replied 9 years ago.
Reply to Davo/diablo666's Post: Checked the dark/green white wire for resistance, checked O.K. Checked on both sides of the plug in between the IPC and the PCM everything checks O.K.
When you unplug the IPC and plug it back in all the gauges come on including the speedometer. Unplugged the speed sensor on the trans and truck would not shift. Plugged it back in and it shifted fine.
Went throught the checks and still cannot find anything.
Also have now noticed that the towhaul button on the shifter works intermittenly, don't know if this has anything to do with it or not.
Expert:  Davo replied 9 years ago.
If it were me I would disconnect the dark green/white wire and run a new temporary one to see if it works after that.Your wire could show continuity and still be shorted to ground or not be able to carry any current.I'm curious as to what your resistance reading was so please post that.
Customer: replied 9 years ago.
Reply to Davo/diablo666's Post: I don't remember exactly what the resistance was, there were 2 dark green/white wires in question. when you put it on one it would jump around, when you put it on the other it would settle out. The wire was showing almost 11 volts with the key on.
Expert:  Davo replied 9 years ago.
You can't do a resistance check on a live circuit/wire the results would be incorrect at best.I could tell you how to voltage drop test the circuit in question but feel if you run a new wire the results will be more conclusive and lead to a faster repair.Did you test the wire for a short to ground or voltage?If you didn't replacing that wire is the easiest step to take.

JustAnswer in the News:

 
 
 
Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.
 
 
 

What Customers are Saying:

 
 
 
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
< Last | Next >
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
  • used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future. David L. Richmond, TX
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil Marysville, CA
  • Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible. Charles Walnut Creek, CA
  • As a single woman, I really appreciate an excellent and affordable opinion.
    Thank you Geordie, I will not hesitate to contact justanswer in the future!
    Sue Charleston, WV
  • Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff. Jim Castleberry, FL
  • Excellent reply, and also very quick. Really sounds like the Expert knows what he is talking about. I will be back to use your service when I need more help with my RV. Dutch USA
 
 
 

Meet The Experts:

 
 
 
  • Chris (aka-Moose)

    Technician

    Satisfied Customers:

    846
    16 years of experience
< Last | Next >
  • http://ww2.justanswer.com/uploads/MU/muddyford/2012-6-13_1204_1.64x64.png Chris (aka-Moose)'s Avatar

    Chris (aka-Moose)

    Technician

    Satisfied Customers:

    846
    16 years of experience
  • http://ww2.justanswer.com/uploads/TE/TedG/2012-6-15_14759_avaLarge.64x64.jpg Ted G.'s Avatar

    Ted G.

    ASE Certified Technician

    Satisfied Customers:

    1596
    20 years auto repair experience, ASE Master Tech, Mechanical Failure consultant, Expert Witness
  • http://ww2.justanswer.com/uploads/joecamel90/2008-11-13_03615_head_shot.jpg George H.'s Avatar

    George H.

    ASE Certified Technician

    Satisfied Customers:

    1311
    ASE Master Tech 15+ yrs, AAS Automotive Technology, Factory trained Asian specialist
  • http://ww2.justanswer.com/uploads/AM/amedee/2013-10-24_23656_Amedee1.64x64.jpg Amedee's Avatar

    Amedee

    ASE Master Tech

    Satisfied Customers:

    2367
    ASE Master Tech advanced level specialist
  • http://ww2.justanswer.com/uploads/SU/supermechanic/2013-8-23_03546_500.64x64.jpg Jerry's Avatar

    Jerry

    Master Mechanic

    Satisfied Customers:

    1906
    ASE master, 30+ years. All makes and models. Trouble shooter, shop forman, service manager
  • http://ww2.justanswer.com/uploads/CR/crzydrvr00/2013-11-3_12123_246347.64x64.jpg Richard's Avatar

    Richard

    ASE Certified Technician

    Satisfied Customers:

    942
    12 years Ford Lincoln/Mercury Jaguar dealership as a technician and shop foreman reparing all makes
  • http://ww2.justanswer.com/uploads/ST/Steve7654/2012-6-5_215929_japic800x660.64x64.jpg Steve's Avatar

    Steve

    Auto Service Technician

    Satisfied Customers:

    1980
    25+ yrs experience as a professional working technician; ASE L1 master technician
 
 
 
Chat Now With An Auto Mechanic
Davo
Davo
1982 Satisfied Customers
ASE Master Technician/Advanced Automotive Diagnostic Technician