Speedometer is DOA!
Thread Starter
|
Posting Guru
Joined: Dec 2012
Posts: 1,644
Likes: 3
From: SW Ohio
Speedometer is DOA!
This past Wednesday coming home from work my EX decided to throw her belt at 85 MPH.
After getting pulled off to the side of the road safely, I popped the hood and saw that the water pump pulley had sheered and the belt had wrapped around the water pump.
I had it towed to a guy that is a seasoned 6.0 L mechanic. He gets it all back together and calls me up and asks if my Speedo was working before it was towed to him.
He said the ECU was seeing the MPH but the speedo was not working. After an hour I get a text saying the speedo was working, but stopped again and the ECU was not seeing MPH.
Besides the speed sensor and the obvious possibility that the tow truck guy could have pinched, ripped or some other terrible thing to the wiring harness, is there any certain area I should look at first?
After getting pulled off to the side of the road safely, I popped the hood and saw that the water pump pulley had sheered and the belt had wrapped around the water pump.
I had it towed to a guy that is a seasoned 6.0 L mechanic. He gets it all back together and calls me up and asks if my Speedo was working before it was towed to him.
He said the ECU was seeing the MPH but the speedo was not working. After an hour I get a text saying the speedo was working, but stopped again and the ECU was not seeing MPH.
Besides the speed sensor and the obvious possibility that the tow truck guy could have pinched, ripped or some other terrible thing to the wiring harness, is there any certain area I should look at first?
Fleet Owner
Joined: Apr 2012
Posts: 27,307
Likes: 549
From: Spanaway
You can with a the right scan tool look at the VSS output.
I would also get under the rear end and look at the diff and
see if the harness get damaged. The rear sensor goes into
the rear diff from the center. Look for the convoluted plastic
jacket and I bet it been crushed.
Sean
I would also get under the rear end and look at the diff and
see if the harness get damaged. The rear sensor goes into
the rear diff from the center. Look for the convoluted plastic
jacket and I bet it been crushed.
Sean
Cargo Master
Joined: Oct 2003
Posts: 2,833
Likes: 5
From: Jefferson, Iowa
Trending Topics
Thread Starter
|
Posting Guru
Joined: Dec 2012
Posts: 1,644
Likes: 3
From: SW Ohio
So I got the truck back today. Speedo was is indeed in operable. Needle does sweep when you do a cluster test.
Then it started raining and the Speedo worked for a bit. Then stopped as things dried out.
ABS is all good no issues there. I did not ask and he did not say what the sensors where reading. He did tell me that he monitored the ABS on the test drive.
The transmission Speed Sensor is reading just fine and is sending a signal to the ECU, which in turn is able to be read by my scan gauge.
I am going to climb under the truck tomorrow after taking care of a few errands and see what I can find out about a wiring issue and replace the rear axle speed sensor.
Then it started raining and the Speedo worked for a bit. Then stopped as things dried out.
ABS is all good no issues there. I did not ask and he did not say what the sensors where reading. He did tell me that he monitored the ABS on the test drive.
The transmission Speed Sensor is reading just fine and is sending a signal to the ECU, which in turn is able to be read by my scan gauge.
I am going to climb under the truck tomorrow after taking care of a few errands and see what I can find out about a wiring issue and replace the rear axle speed sensor.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Fleet Owner
Joined: Apr 2012
Posts: 27,307
Likes: 549
From: Spanaway
If the SGII is seeing speed then the problem is between the PCM and
the speedometer. They read from the same place. BTW It's not the in
transmission. It in the rear diff. The transmission does not have a speed
sensor for speed.
One thing you could check is if the plugs on the top of the cluster are
both plugged in and not loose.
Sean
the speedometer. They read from the same place. BTW It's not the in
transmission. It in the rear diff. The transmission does not have a speed
sensor for speed.
One thing you could check is if the plugs on the top of the cluster are
both plugged in and not loose.
Sean
Thread Starter
|
Posting Guru
Joined: Dec 2012
Posts: 1,644
Likes: 3
From: SW Ohio
Well just an update.
The speedometer started working again and has been for the last 4 days. I now have an ABS light that comes and goes. I took it up to the local Advance store and it has a code for the left front ABS sensor. I also have what sounds like a bearing rumble. I just replaced the HUB bearings when I did the ball joints. When it warms up this up coming weekend, I will pull the HUB and get a replacement exchange from the parts store.
The speedometer started working again and has been for the last 4 days. I now have an ABS light that comes and goes. I took it up to the local Advance store and it has a code for the left front ABS sensor. I also have what sounds like a bearing rumble. I just replaced the HUB bearings when I did the ball joints. When it warms up this up coming weekend, I will pull the HUB and get a replacement exchange from the parts store.
Thread
Thread Starter
Forum
Replies
Last Post
MX_Fyrcaptain
1999 - 2003 7.3L Power Stroke Diesel
13
May 8, 2009 10:52 PM