C5 Tachometer Issue
Thread Starter
Intermediate
Joined: Jul 2004
Posts: 36
Likes: 2
From: Maryland
C5 Tachometer Issue
I have a 2001 Coupe with an issue with the HUD instrument cluster. The issue is that the tachometer doesn't always count. The needle and HUD go full clockwise when the engine is started but most of the time instead of the needle and HUD settling on the idle RPM, it falls back to zero. I can tap the top of the dash and get it to count but eventually it will stop again.
I have removed the cluster and sent it to AER Technologies. Their bench testing found no fault in the cluster. The AER tech suggested re-homing the wires in the multipin plug. Does any one know what color wire out of the ~20 wires terminating in the plug feeds the data to the tach?
Additionally, there is a gray cover over the back of the plug keeping all wires at a right angle as they enter the rear of the plug. Can this cover be safely removed in order to re-home the wires?
Is there any other suggestion that I might try to restore the tachometer to full operations?
Appreciate assistance...
I have removed the cluster and sent it to AER Technologies. Their bench testing found no fault in the cluster. The AER tech suggested re-homing the wires in the multipin plug. Does any one know what color wire out of the ~20 wires terminating in the plug feeds the data to the tach?
Additionally, there is a gray cover over the back of the plug keeping all wires at a right angle as they enter the rear of the plug. Can this cover be safely removed in order to re-home the wires?
Is there any other suggestion that I might try to restore the tachometer to full operations?
Appreciate assistance...
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
Not at home now but I can get you the connector pin outs between the HUD and the IPC if no one beats me to it. It sounds like you may have a HUD issue and not an IPC issue. A loose pin would be nicer.
You say needle and HUD, what do you mean by needle?
You say needle and HUD, what do you mean by needle?
Drifting
Joined: Feb 2008
Posts: 1,596
Likes: 67
From: Bahama North Carolina
I think he means the tach in the dash so it wouldn't be just a HUD issue.
Thread Starter
Intermediate
Joined: Jul 2004
Posts: 36
Likes: 2
From: Maryland
I mean the needle on the tach guage. The guage and HUD show the same display. They both either count the RPMs or don't count the RPMs.
Looking for other ideas to pin down the aperiodic problem.
Looking for other ideas to pin down the aperiodic problem.
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
The IPC connector pin for engine speed is A17 (white wire). It is the only white wire at the end of the two rows of pins. If you need a view of the connector let me know. There are other white wires, but none on the ends.
I am sure the cover on the connector can be removed. I have done that to remove pins on the BCM connector. Just never seen this connector.
I am sure the cover on the connector can be removed. I have done that to remove pins on the BCM connector. Just never seen this connector.
Thread Starter
Intermediate
Joined: Jul 2004
Posts: 36
Likes: 2
From: Maryland
Based on your comment, I located a diagram of the IPC connector at http://corvetteforum.shelor.net/Diag...PC_Pinout.html. It clearly shows the pin allocations and wire colors. A17 is under the cover so it has to be removed before resetting the WHT (Engine Speed Signal) wire.
Thanks for the help.
Thanks for the help.
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
Do you know how to release the pin? If not let me know. It is simple with a small round pin from the back of the connector. You can view a video of this by going to eBay and looking at the LMC5. The video covers the whole process. They use a small allen key. Good luck.
Thread Starter
Intermediate
Joined: Jul 2004
Posts: 36
Likes: 2
From: Maryland
Could you send me the link for the video? There's a lot on eBay and all I found was a "LMC5 MODULE - 97-04 C5 CORVETTE STEERING COLUMN LOCK BYPASS". I don't want to force something and get into deep dodo.
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Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
You had it right but here is the link. Just scroll down the ad until you see the video.
http://www.ebay.com/itm/LMC5-MODULE-97-04-C5-CORVETTE-STEERING-COLUMN-LOCK-BYPASS-FIX-REPAIR-/231054138991?pt=Motors_Car_Truck_Parts_Accessories&hash=item35cbe65e6f&vxp=mtr
http://www.ebay.com/itm/LMC5-MODULE-97-04-C5-CORVETTE-STEERING-COLUMN-LOCK-BYPASS-FIX-REPAIR-/231054138991?pt=Motors_Car_Truck_Parts_Accessories&hash=item35cbe65e6f&vxp=mtr
Thread Starter
Intermediate
Joined: Jul 2004
Posts: 36
Likes: 2
From: Maryland
My first search located an eBay link to the LMC5 kit only. Subsequent searches did locate the associated video. BTW, I wish I knew of this kit when my column lock went out. Thanks for the follow up. Once AER Technologies returned the cluster, after finding nothing wrong with it, the biggest help in resolving this tach issue was the IPC pinout diagram: http://corvetteforum.shelor.net/Diag...PC_Pinout.html. It not only gave the voltage levels for A17 but also identified B13 and B15 as grounds. I found the WHT wire loose in the A17 socket. Removing it, using the LMC5 video, allowed me to adjust the barb on the crimped connector. Once reseated, it no longer moved slightly in the socket. Driving the car with one hand moving the wiring harness or the IPC confirmed that the tach fully was operational.
Job done. Thanks for the help.
Job done. Thanks for the help.