code 634
Thread Starter
|
5th Wheeling
Joined: May 2024
Posts: 32
Likes: 3
code 634
Hello,
On my 1992 F150, the check engine light comes on after driving for 5 minutes.
After checking the OBD2, code 634 is displayed (shift position sensor voltage higher or lower than expected).
Do you have any ideas on what I should do?
Thanks.
On my 1992 F150, the check engine light comes on after driving for 5 minutes.
After checking the OBD2, code 634 is displayed (shift position sensor voltage higher or lower than expected).
Do you have any ideas on what I should do?
Thanks.
Logistics Pro
Joined: Aug 2014
Posts: 3,547
Likes: 845
What code reader are you using?
the Manual Lever Position Sensor(MLPS), or wirining.
Check the connection.
There is an upgraded MLPS, as the older ones allowed water intrusion.
Lots of posts with how to test it:
https://www.ford-trucks.com/forums/1...l#post16092808
the Manual Lever Position Sensor(MLPS), or wirining.
Check the connection.
There is an upgraded MLPS, as the older ones allowed water intrusion.
Lots of posts with how to test it:
https://www.ford-trucks.com/forums/1...l#post16092808
Fleet Owner
Joined: Oct 2005
Posts: 20,783
Likes: 1,749
From: Kentucky
The MLPS is behind the shifter lever arm:
There is an adjustment notch to help aligning it:
similar to this one
Ford updated the MLPS and connector in 1995 I believe. You may want to upgrade yours to the newer style.
There is an adjustment notch to help aligning it:
similar to this one
Ford updated the MLPS and connector in 1995 I believe. You may want to upgrade yours to the newer style.
Hotshot
Joined: Jul 2020
Posts: 10,268
Likes: 2,563
From: Near Salt Lake City
Do some research concerning that MLP switch connector
Ford had us switch to an updated sensor and a new connector because those old ones were no good
That means simply replacing the MLP may do NOTHING for you
I
Ford had us switch to an updated sensor and a new connector because those old ones were no good
That means simply replacing the MLP may do NOTHING for you
I
Trending Topics
Thread Starter
|
5th Wheeling
Joined: May 2024
Posts: 32
Likes: 3
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Logistics Pro
Joined: Aug 2014
Posts: 3,547
Likes: 845
You need to diagnose IF the problem is your MLPS.
If you have an older style MLPS, it is recommended to replace it with a newer style.
You probably have to manually clear the code. The scan tool you have should be able to clear it.
If you have an older style MLPS, it is recommended to replace it with a newer style.
You probably have to manually clear the code. The scan tool you have should be able to clear it.
Fleet Owner
Joined: Oct 2005
Posts: 20,783
Likes: 1,749
From: Kentucky
I do not recall if you stated Code 634 was appearing in the KOEO tests and/or Stored Code display. If the latter, clear the Stored Codes. Did you properly align the MLPS as discussed previously?
Once any Stored Codes are cleared, you can test the MLPS. Here is the MLPS Test procedure. Focus on the Transmission Circuit resistance values:
Once any Stored Codes are cleared, you can test the MLPS. Here is the MLPS Test procedure. Focus on the Transmission Circuit resistance values:
Fleet Owner
Joined: Oct 2005
Posts: 20,783
Likes: 1,749
From: Kentucky
Refer to page 37 of the manual for how to clear Stored Codes. Changing the MLPS pins to the new connector is a one-for-one swap, usually not that difficult to do. I asked if you properly aligned the MLPS (S = Sensor) as discussed in previous posts.