Today we're going to be putting an APPS sensor on an '03 Dodge five speed. This is a 250
horsepower truck. This truck came in and you just start out going down the road and the
truck would just fall completely on its face. Customer might've thought it had a fuel issue.
After we brought it in and checked the codes on it, we noticed that it's got a P2122 and
a P2121, those are both APP sensor codes. Drove the truck down the road and we watched
the APP sensor sweep on the data display. The first thing that you'll come to is you'll
notice that when you're doing a data read with like, this is Snap-On SOLUS, is your
APPS percentage. You can be going down the road at 50% throttle and this will just drop
to zero and the truck will fall and it'll pick back up. So we've definitely got an APP
sensor problem.
Now as far as our TPS, however you want to call it, TPS or APPS, sensors that we offer
on the website, we offer a line power. We've got them in two different models. We have
them like what we're going to install today. This will be just the potentiometer part of
the APP sensor. This is an Alliant Power, AP-63458. This works on the VP and the common
rail trucks as well. This is actually just the sensor and we're going to show you how
to install it today. Now we already have these preassembled, the bell crow, what they out
the call bell crank assembly, we offer those on the website as well.
So let's get started with our install. This assembly on the front of the engine is our
TPS sensor or APPS sensor or APPS. This is on the '98 and a half to '04 Dodges the '98
and a half to '02 VP trucks. It's again on the front of the engine, on the driver's side
of the engine, on the '03, '04 trucks same location, front of the engine, driver's side
of it. This is only on the common rail trucks, the '03 and '04s that are the 250 or the 305
horsepower. So if you got a 325 horsepower '04 and a half, you will not have this.
The first thing we're going to do today is we're going to loosen up the three bolts that
hold the housing to the motor. What that's going to allow us to do is to get access to
the front screw. This is where your APPS or TPS sensor is located. It is on the driver's
side front of the engine. Now the '98 to '02 VP 44 trucks all have this as well as do the
'03 and '04 250 and 305 horsepower common rail trucks. So again, it's on the front driver's
side of the engine. What we're going to do first off is we're going to take the three
13 metric bolts out that hold it to the front of the engine, and we're just going to loosen
them up and that's going to give us some slack to be able to get to our front cover screw.
Okay. Now we're going to remove our cover screw to give us access to our six bolts holding
the APPS bracketry on. The first screw is on the top of the APPS, the box and it's a
screw with an insert, so once you loosen it up, you should be able to pull it out as one
little assembly there. Then that gives us access to our front screw on our cover. Now,
that's got both of our screws out. I'm going to put a couple of bolts back in the APPS.
To
pull the cover off, there's two clips on the front of it. You can pull it and just slide
it straight down and pull it right out.
Okay. Now you can see the location of the six bolts that hold the assembly onto the
housing. Three bolts here on the top, three bolts on the bottom and that's going to expose
our potentiometer or APPS sensor itself actually. We're going to remove those real quick. 10
metric. A little bit of an extension makes this
a little bit easier. We've got the APPS the drive assembly off the housing. Now there's
two torque bolts that hold the APPS potentiometer on, they are a T20 Torx and what we're going
to do is just get them started and loosen them. There is an electrical connector on
the bottom of the potentiometer. We're going to go ahead and unhook it once we get this
loose. Now we can begin to remove our potentiometer. I don't know what's wrong with that thing
Adam. This screw ain't wanting to come out. Got it that time.
What's it snapping you reckon?
I don't know what it was, just old. All right. This is the potentiometer itself. Now you
can see on here it says .439 voltage direct current. That is where this would be set up
at zero pedal position. Now I'm going to teach you how to back probe the wires and setting
this new one up, but this one should've supposed to been set up at a .439. When we probed it
was about .25 so it was a little bit off already. So that's good. We know the pedal position
sensor is bad.
So now we're going to install our new one. All right. To install your new one, you'll
see a little tongue there the potentiometer goes on. You simply slide it onto that and
just kind of generally get it pointed straight down. Then install your bolts, your Torx bolts
back. Now you'll want to leave these loose going forward into this because we will be
doing some adjusting here. Now this potentiometer in this package is rated for .55 volts at
idle and it will be plus or minus a .05 volts. So what we're going to do now is we're going
to get this just snug down and then we're going to test it to see what our voltage is.
Okay, now that we have our potentiometer on, what we're going to do is we're just going
to hook our harness back up and we are going to go in and we're going to set up our voltages
on this APPS. Now the way that we're going to do that is we're going to go in and turn
the key on inside the truck and then we're going to come out here and we're going to
back probe the number three wire in this harness. Let me get this out of your way so you can
see it. The number three wire in this harness, which is your yellow wire on the outside closest
to the firewall. So it's the yellow wire on the outside truck pointing closest towards
the driver's fender well and then closest to the back of the truck. That's how it hooks
up to the APPS.
So what we're going to do is we're going to back probe it. We're just going to put our
volt meter in here and then we're going to hook it back to her potentiometer, just like
that. Everything clicks. Now we'll get inside the truck, turn the truck on, and we'll check
our voltage and set out APPS. Now we're going to set up the potentiometer. What we have,
we've left this loose on the Torx bolts. Okay. The wiring harness is hooked up. The key is
on in the truck. We want to set this potentiometer, this APPS to .55 volts. Our range on that
you can miss it by a .05 volts. So what we're going to do is we're going to be back probing
the number three wire, which is the yellow wire coming out of the harness. It will be
the one closest to the driver's fender and closest to the firewall, so out and back.
All right, so we're just going to back probe it now. All right Jimmy me see what you've
got right there. Now as you can see on the volt meter, we're at .47, .39. So we need
to go the other way. .55, perfect. All right. We've got Adam over here on the Torx wrench,
he's going to get her top one for us. Hold on a just a second, man. Let me get it perfect.
Perfect. Get it right there. All right. Tighten it. Tighten it. That's it. Perfect.
Now you can see you've got to have a couple of guys to help you do that. It's a little
bit more technical. Now again, like we were talking about in the first part of the video,
if you buy a APPS sensor from us already put together, they're a little bit more expensive,
but this is already done for you. So we're going to tighten this down. You've got a torque
spec of 150 inch pounds on this to tighten it down. Then you'll want to go back and just
double check yourself again. The yellow wire on the outside closest to the firewall. Check
it, make sure that you're sitting at around .55. I'm not making good contact in there.
There it is. All right, perfect. All right, she's good to go. Now we're going to torque
it down and put her housing back together.
All right. Now reinsert your six bolts that hold the sensor to the housing. This is real
easy, just the installation of this and just the reverse of removal. Well put our front
cover back on the APPS and it just goes around everything. It goes up to the front and snaps
on. Your two Phillips screw push pins. Put those back in. One in the back of the sensor
housing, one in the front. All right.
Hey Jimmy go cut that other light on over there. You'll need something to poke it with.
Grab that Torx wrench right off the front bud. That'll work too.
Thou shalt have $10,000 in your pocket.
That's not going to leak.
All right. Now our 13 on the housing. 13s on the housing, tighten those down. Okay,
now we're going to move to the cab. We're going to hook it up on sensor or hook it up
on scanner and make sure everything's okay. Okay, now we've got our APPS sensor in. Now
this is very important. First step when you get back in the truck, you turn the key off.
After your installation, you've been checking your sweeps on your potentiometer. First thing
you want to do is turn the key on in the truck, get in the truck and very slowly depress the
accelerator pedal from zero all the way to 100%, all the way to the floor and then let
up on it and turn the key off. This will set up your potentiometer. So now what we're going
to do first is we're going to start to truck. Make sure everything's working. That's perfect.
It idles correctly. It takes prop throttle correctly, everything's good. We're going
to clear the codes out and that completes our installation.
Now again, ordering this line power potentiometer, this is going to save you some money, but
as you saw today, it's kind of a labor intensive installation, so our already assembled APPS
sensors are right around the 425 or I'm sorry, 440 to $450 range. Just depending on if you
have a manual shift truck or you have an automatic truck. They're really easy to install. They're
just to unbolt them, unbolt the 13 metric bolts, bolt the new and back in, you're ready
to go. Set up your sweeps. Maybe take you 10 minutes to do your installation. This installation
is a little bit more labor intensive, but it's going to save you a couple of hundred
dollars. So hope that helps you out. Again, this is a line power, APPS throttle position
sensor or accelerator position sensor installation. If you have any questions for anything, let
us know. Thank you.