Speedometer, RPM, PRND not working

Discussion in 'GMC Truck Forum' started by James L, Jan 20, 2010.

  1. James L

    James L Full Member

    Joined:
    Jan 20, 2010
    Messages:
    10
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Eastern North Carolina
    Hello

    1995 GMC C1500, 5.7L, AT, 198K

    Speedometer, RPM gauge and PRND light are not working. Checked fuses and all are ok. inspected wires, cleaned vss at AT. Reset ECM. No extra electrical accessories installed.

    I am getting a "check gauges" light flasing on instrument cluster. Did the code scan and I am getting codes 66 (trans 3-2 shift control soleniod circuit problems) and code 67 (torg conv soleniod circuit problems)

    Transmission shifts ok.

    I did alot of searching and reading on this forum; bad cluster? bad vss?
    bad vss sender?

    Thanks
     
  2. davbell22602

    davbell22602 Senior Member

    Joined:
    Nov 11, 2009
    Messages:
    4,173
    Likes Received:
    23
    Trophy Points:
    0
    Location:
    winchester, va
    Welcome to the forum. What about Vehicle Speed Sensor?
     
  3. James L

    James L Full Member

    Joined:
    Jan 20, 2010
    Messages:
    10
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Eastern North Carolina
    Yes thinking about the varible speed sensor (vss) my factory service/elec manual talks about a test; jack up rear wheels start eng, put in gear check for voltage drops yes/no - circuit, vss or vss sender?- or ohms go up as speed increases vss is good.

    when i undid the vss electrical plug at trans to clean, it had some oil/trans fluid in the socket?
     
  4. bradrhale

    bradrhale Senior Member

    Joined:
    Apr 11, 2006
    Messages:
    11,170
    Likes Received:
    117
    Trophy Points:
    0
    Occupation:
    County Environmental Health Inspector
    Location:
    Texas
    VSS has nothing to do with the tach or the PRND21. i would suspect the cluster.
     
  5. James L

    James L Full Member

    Joined:
    Jan 20, 2010
    Messages:
    10
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Eastern North Carolina
    should I pull the cluster? if so what to check for; clean plugs? look for burn circuit boards/wires? can the cluster be bench tested?

    can these cluster circuit boards be resoldered? are these common cluster problems a resolder problem?

    salvage yard cluster or send off to repair such as United Radio in NY?

    thanks
     
  6. bradrhale

    bradrhale Senior Member

    Joined:
    Apr 11, 2006
    Messages:
    11,170
    Likes Received:
    117
    Trophy Points:
    0
    Occupation:
    County Environmental Health Inspector
    Location:
    Texas
    you mentioned the check gauges. do the other gauges read accurate or where they are supposed to be such as your temp, oil, and other such?? those 2 codes should have no affect on the check gauges light and this is why i am asking about the others. you can try checking the connections as a first step but may have to look into maybe a new cluster. there was a TSB for that cluster if im not mistaken and demanded a new cluster. but again, you may want to check on that for your model year.
     
  7. James L

    James L Full Member

    Joined:
    Jan 20, 2010
    Messages:
    10
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Eastern North Carolina
    Brad,

    temp, oil, fuel, and battery charge gauges do work (accurate), as does the gauge lights.

    a week ago the PRND orange inicator went out in the cluster, then a few days later the speedometer and RPM went out.

    they work sometimes, the PRND will light up and the speedo and RPM will work and then go out intermitently.

    was there a factory recall or just a TSB?

    what is the bad part on these clusters?

    thanks
     
  8. bradrhale

    bradrhale Senior Member

    Joined:
    Apr 11, 2006
    Messages:
    11,170
    Likes Received:
    117
    Trophy Points:
    0
    Occupation:
    County Environmental Health Inspector
    Location:
    Texas
    i really cant say as i just dont remember. (suffer from CRS) being an intermittent problem, i would definitely check connections.
     
  9. James L

    James L Full Member

    Joined:
    Jan 20, 2010
    Messages:
    10
    Likes Received:
    0
    Trophy Points:
    0
    Location:
    Eastern North Carolina
    Checked/wiggled vss wiring/sender above blower motor, also rechecked all fuses. no change.

    Pulled instrument cluster, inspected. no burnt areas, looked ok. cleaned connections and reinstalled. started engine and PRND, RPM worked for a second and then stopped. Every time I restart it works and then stops working.

    Called United Radio in NY, will repair cluster for $175, 1 year guarntee, 3 day turnaround. A+ used cluster at local salvage yard $60.
     
  10. Faxcion

    Faxcion Senior Member

    Joined:
    Jun 18, 2009
    Messages:
    65
    Likes Received:
    1
    Trophy Points:
    0
    Occupation:
    Outdoor Power Equipment Specialist at Lowe's
    Location:
    Calico Rock Ar.
    I dont think they've fixed the cluster problems ever, because my 03 sierra's spedo, oil pressure, and rpm gauges are strait up dead. .. atleast my engine works *knocks on wood*
     

Share This Page