QuestionQUESTION: The tach on my envoy acts intermittant. It will work properly for awhile then fall to zero. This just started. the Envoy has 100,000 miles.
ANSWER: if the vehicle continues to operate properly when this happens I would suspect the cluster is faulty. If the PCM was not getting the correct RPM reading from the egine itself then you would be setting a check engine light
---------- FOLLOW-UP ----------
QUESTION: So do i need to replace the cluster? If so where can I find out how? Im new to doing the repairs and dont want to it to get out of hand.
Thank You for the fast response. I just found this site. wish i had found it sooner.
ANSWER: Cluster should not be too hard to remove, once you remove the bezel there are a few screws that hold it in place and a plug on the back. I would first however find out where your are either going to get a replacement from or if you are going to have a shop repair it, once you either get it refurbished or replaced, it may need to be programmed for it to function properly, you most likely will need to have a dealer do this programming, in necessary
---------- FOLLOW-UP ----------
QUESTION: I probably should have said this earlier, i apologize if it makes a difference. Does it matter that the cluster is not digital, but has regular guages.
Answerno its not an issue here are some step by step instructions
Remove the left closeout insulator panel. Refer to Instrument Panel Insulator Panel Replacement - Left Side .
Remove the knee bolster trim panel. Refer to Driver Knee Bolster Panel Replacement .
Remove the instrument panel cluster (IPC) bezel. Refer to Instrument Panel Cluster Trim Plate Bezel Replacement .
Remove the screws retaining the IPC to the I/P.
Partially remove the IPC from the I/P in order to gain access to the electrical connector.
Disconnect the electrical connector from the IPC.
Remove the IPC from the I/P.
Position the IPC to the I/P.
Connect the electrical connector to the IPC.
Install the IPC to the I/P.
Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Install the screws to the instrument panel cluster.
Tighten
Tighten the screws to 2.5 N·m (22 lb in).
Install the IPC bezel. Refer to Instrument Panel Cluster Trim Plate Bezel Replacement .
Install the knee bolster trim panel. Refer to Driver Knee Bolster Panel Replacement .
Install the left closeout insulator panel. Refer to Instrument Panel Insulator Panel Replacement - Left Side .
If installing a new IPC. Refer to Service Programming System (SPS) in Programming.
the new cluster will need to be reprogrammed
