Speed-o-meter
Thread Starter
Racer
Joined: Nov 2016
Posts: 351
Likes: 13
From: Payson AZ
Speed-o-meter
About a month ago my speedometer quit working and when the car was shut off and restarted it worked fine.
Last week it quit working again and now restarting does nothing.
Although the speedometer is not working the cruise control works and displays your speed when you set it.
Any ideas what to start with in diagnosing the problem?
I did a search but didn't find anything related.
Last week it quit working again and now restarting does nothing.
Although the speedometer is not working the cruise control works and displays your speed when you set it.
Any ideas what to start with in diagnosing the problem?
I did a search but didn't find anything related.
5th Gear
Joined: Jan 2017
Posts: 5
Likes: 0
From: New Orleans LA
I have the exact same issue in my 99, restarting the car fixed it the first couple of times, then last week it went out and hasnt started back again...no new codes and I dont have a HUD..anyone have any ideas where to start looking for the issue? Possibly related, my fuel gauge went out around the same time the speedo started acting up. I know this is the sending unit on one of the tanks I just havent got to it working on it yet.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Any thing wrong with the fuel level system is PCM monitored and will usually set a DTC. Clear all the DTCs and see what comes back. Get a meter out and see if all the supply voltages & Grounds are there.
Bill
Here is your shematic:
Bill
Here is your shematic:
Safety Car
Joined: Dec 2010
Posts: 3,938
Likes: 498
From: Fords, NJ
I had to replace all 6 stepper motors in my 03 Silverado. While i was at it I did a LED swap for the dash lights as well.
And you'll noticed the Oil Pressure is pegged....C5's aren't the only ones with oil sending unit problems....
It's been replaced since this picture was taken ! 
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Thread Starter
Racer
Joined: Nov 2016
Posts: 351
Likes: 13
From: Payson AZ
The car isn't throwing any codes and I do not have a HUD. When I set the cruise it tells the speed in the DIC area
Sometimes it works and sometimes it doesn't. If it don't most times shutting it down and restarting makes it work.
Sometimes it works and sometimes it doesn't. If it don't most times shutting it down and restarting makes it work.
Last edited by C5 Newb; May 15, 2017 at 12:33 AM.
Drifting
Joined: Nov 2014
Posts: 1,978
Likes: 110
From: Switzerland
Thread Starter
Racer
Joined: Nov 2016
Posts: 351
Likes: 13
From: Payson AZ
Thanks Bill for the wiring schematic. I am a fair mechanic but suck at electrical stuff and I am afraid I don't even know what to look for on the diagram. I am not good with wiring diagrams...
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
LOL!!!!! I here you. Sometime we just have to start with the BASICS. Look at the fuse and you will see that it is supplied by something called "HOT in ON & Start"
That means it is supplied by a 12 VDC supplied by the IGNITION SWITCH. Our C5 Ignition Switchs are widely known to be a source of voltage output problems. The contacts inside get burnt and worn and the voltage out of the switcn can be less than 12 VDC. Our modules DO NOT like less than adeaquate supply voltages.
Some module have dual supply voltage and the OTHER voltage is a dirrect battery feed "Hot at ALL TIMES"
On top of the fuses are two small slots. Use a DC Volt meter and read each slot to chassis or battery ground with the ignition switch ON. Especially measure it when the gages are whacked out. If it is less than full battery voltage, the switch could be causing issues with the gages.
Bill
That means it is supplied by a 12 VDC supplied by the IGNITION SWITCH. Our C5 Ignition Switchs are widely known to be a source of voltage output problems. The contacts inside get burnt and worn and the voltage out of the switcn can be less than 12 VDC. Our modules DO NOT like less than adeaquate supply voltages.
Some module have dual supply voltage and the OTHER voltage is a dirrect battery feed "Hot at ALL TIMES"
On top of the fuses are two small slots. Use a DC Volt meter and read each slot to chassis or battery ground with the ignition switch ON. Especially measure it when the gages are whacked out. If it is less than full battery voltage, the switch could be causing issues with the gages.
Bill
Thread Starter
Racer
Joined: Nov 2016
Posts: 351
Likes: 13
From: Payson AZ
LOL!!!!! I here you. Sometime we just have to start with the BASICS. Look at the fuse and you will see that it is supplied by something called "HOT in ON & Start"
That means it is supplied by a 12 VDC supplied by the IGNITION SWITCH. Our C5 Ignition Switchs are widely known to be a source of voltage output problems. The contacts inside get burnt and worn and the voltage out of the switcn can be less than 12 VDC. Our modules DO NOT like less than adeaquate supply voltages.
Some module have dual supply voltage and the OTHER voltage is a dirrect battery feed "Hot at ALL TIMES"
On top of the fuses are two small slots. Use a DC Volt meter and read each slot to chassis or battery ground with the ignition switch ON. Especially measure it when the gages are whacked out. If it is less than full battery voltage, the switch could be causing issues with the gages.
Bill
That means it is supplied by a 12 VDC supplied by the IGNITION SWITCH. Our C5 Ignition Switchs are widely known to be a source of voltage output problems. The contacts inside get burnt and worn and the voltage out of the switcn can be less than 12 VDC. Our modules DO NOT like less than adeaquate supply voltages.
Some module have dual supply voltage and the OTHER voltage is a dirrect battery feed "Hot at ALL TIMES"
On top of the fuses are two small slots. Use a DC Volt meter and read each slot to chassis or battery ground with the ignition switch ON. Especially measure it when the gages are whacked out. If it is less than full battery voltage, the switch could be causing issues with the gages.
Bill
Thanks Bill, I will start there.
Drifting
Joined: Dec 2003
Posts: 1,895
Likes: 84
From: Darien IL
A possibility is the VSS. It also controls reverse lockout, automatic door locking, HUD and cruise control. All of those stopped working at the same time my speedometer quit. My speedometer would work intermittently.
Thread Starter
Racer
Joined: Nov 2016
Posts: 351
Likes: 13
From: Payson AZ
LOL!!!!! I here you. Sometime we just have to start with the BASICS. Look at the fuse and you will see that it is supplied by something called "HOT in ON & Start"
That means it is supplied by a 12 VDC supplied by the IGNITION SWITCH. Our C5 Ignition Switchs are widely known to be a source of voltage output problems. The contacts inside get burnt and worn and the voltage out of the switcn can be less than 12 VDC. Our modules DO NOT like less than adeaquate supply voltages.
Some module have dual supply voltage and the OTHER voltage is a dirrect battery feed "Hot at ALL TIMES"
On top of the fuses are two small slots. Use a DC Volt meter and read each slot to chassis or battery ground with the ignition switch ON. Especially measure it when the gages are whacked out. If it is less than full battery voltage, the switch could be causing issues with the gages.
Bill
That means it is supplied by a 12 VDC supplied by the IGNITION SWITCH. Our C5 Ignition Switchs are widely known to be a source of voltage output problems. The contacts inside get burnt and worn and the voltage out of the switcn can be less than 12 VDC. Our modules DO NOT like less than adeaquate supply voltages.
Some module have dual supply voltage and the OTHER voltage is a dirrect battery feed "Hot at ALL TIMES"
On top of the fuses are two small slots. Use a DC Volt meter and read each slot to chassis or battery ground with the ignition switch ON. Especially measure it when the gages are whacked out. If it is less than full battery voltage, the switch could be causing issues with the gages.
Bill
Everything works in the car BUT the speedometer when driving.
Speedometer DOES go through it's full sweep when you turn the key ON.
I don't have HUD.
When your driving and set the cruise control the speed shows in the LCD display.
Cruise control works.
Reverse lockout works.
Just wanted to clarify what is working and what isn't for everyone who may be following this including you BIll.
Thread Starter
Racer
Joined: Nov 2016
Posts: 351
Likes: 13
From: Payson AZ
LOL!!!!! I here you. Sometime we just have to start with the BASICS. Look at the fuse and you will see that it is supplied by something called "HOT in ON & Start"
That means it is supplied by a 12 VDC supplied by the IGNITION SWITCH. Our C5 Ignition Switchs are widely known to be a source of voltage output problems. The contacts inside get burnt and worn and the voltage out of the switcn can be less than 12 VDC. Our modules DO NOT like less than adeaquate supply voltages.
Some module have dual supply voltage and the OTHER voltage is a dirrect battery feed "Hot at ALL TIMES"
On top of the fuses are two small slots. Use a DC Volt meter and read each slot to chassis or battery ground with the ignition switch ON. Especially measure it when the gages are whacked out. If it is less than full battery voltage, the switch could be causing issues with the gages.
Bill
That means it is supplied by a 12 VDC supplied by the IGNITION SWITCH. Our C5 Ignition Switchs are widely known to be a source of voltage output problems. The contacts inside get burnt and worn and the voltage out of the switcn can be less than 12 VDC. Our modules DO NOT like less than adeaquate supply voltages.
Some module have dual supply voltage and the OTHER voltage is a dirrect battery feed "Hot at ALL TIMES"
On top of the fuses are two small slots. Use a DC Volt meter and read each slot to chassis or battery ground with the ignition switch ON. Especially measure it when the gages are whacked out. If it is less than full battery voltage, the switch could be causing issues with the gages.
Bill
I don't mean to sound retarded here but are you saying to check fuse # 13 or all the fuses ?
Thread Starter
Racer
Joined: Nov 2016
Posts: 351
Likes: 13
From: Payson AZ
Ok. I checked for codes even though the check engine light wasn't on. The LCD display always shows ABS, Traction control and active handling so I always clear those.
But when I checked for codes this time it had a bunch.
A couple are known problems with the BPMV having a stalled motor but Not sure if any of the others have anything to do with the speedometer.
Here they all are.....
B2253 Key Cylinder Switch Circuit - H ?? For some reason you can pull the key and it keeps on running, I did this the other day to show my brother, probably what cause this...
B2723 PASS-Key Detection Circuit - H ?? Same as above??
C1242 BPMV Pump Motor Ground Circuit Open -H C - Known issue
C1243 BPMV Pump Motor Stalled - H C - known issue
C1247 Brake Pressure Differential Switch Activated - H - Brake bleeding the other day?
P0420 Catalyst System Low Efficiency Bank 1 - H C - Cat going bad?
P0654 Engine Speed Output Circuit - H - ??? Cluster out the other day?
P0804 Skip Shift Lamp Control Circuit - H - Bulb out of circuit board?? (New bulbs ordered)
U1096 Loss of Communications with IPC - H - From removal of gauge cluster??
But when I checked for codes this time it had a bunch.
A couple are known problems with the BPMV having a stalled motor but Not sure if any of the others have anything to do with the speedometer.
Here they all are.....
B2253 Key Cylinder Switch Circuit - H ?? For some reason you can pull the key and it keeps on running, I did this the other day to show my brother, probably what cause this...
B2723 PASS-Key Detection Circuit - H ?? Same as above??
C1242 BPMV Pump Motor Ground Circuit Open -H C - Known issue
C1243 BPMV Pump Motor Stalled - H C - known issue
C1247 Brake Pressure Differential Switch Activated - H - Brake bleeding the other day?
P0420 Catalyst System Low Efficiency Bank 1 - H C - Cat going bad?
P0654 Engine Speed Output Circuit - H - ??? Cluster out the other day?
P0804 Skip Shift Lamp Control Circuit - H - Bulb out of circuit board?? (New bulbs ordered)
U1096 Loss of Communications with IPC - H - From removal of gauge cluster??
Last edited by C5 Newb; May 21, 2017 at 08:00 PM.