2002 Ford F250, No Trailer Turn Signals

This 2002 Ford F250 came in with the complaint that the turn signals did not work at the trailer pigtail connector. The turns signals on the truck worked okay. Well after examining a wiring diagram I found that fuse number 6 in the interior fuse box supplies power to the right and left, trailer tow relays. I checked the fuse and it was good.

I then checked for power at the relays on terminal #3 which is supplied by the interior fuse #6. No power, must have a broken wire somewhere.

I dropped the interior fuse box so that I could access the wiring behind it. Checking for power on the dark green/orange wire I found that there was power present.

I went back to the relay box under the hood. I released the clip that held it down and removed the rear cover so that I could get to the wiring. Again I confirmed no power was present.

I tried wiggling the wires to see if power would come back but no such luck. I then started tracing the wiring and found that the wires went back to a series of junction connectors at the driver’s inner fender panel. Further inspection found that the wire had been rubbing on a hose and had corroded in (the light green spot) half.

DSC02641

I opened the harness cut out the faulty wire and added a new piece. Another one done.

1989 Ford Crown Victoria, No Charge Condition, Alternator Wiring

This 1989 Ford Crown Victoria came in with a no charge condition and a customer that refused to listen. He came in a couple of days earlier and stated that he had replaced the alternator and the voltage regulator and the charge light was still on. I explained to him that he more than likely had the wires hooked up incorrectly at the rear of the alternator and if he would check and repair it it would be okay. He would probably have to replace the regulator again though because hooking up the wiring wrong would generally blow the regulator. He said he checked the wiring and it was oaky so he brought it to me. Wrong, wrong , wrong. Why do people not listen when you tell them what to do. See the terminal stud with the white plastic insulator. That is the field terminal. The alternator cannot charge with no input to this terminal. Do You see a wire attached to this terminal, No.

Yeh , I think I should connect the field wire to the ground stud or maybe the field terminal to the stator stud and the stator terminal wire to the ground stud, that makes sense. You know most people have cameras to take pictures with and everybody can find a piece of paper and a pen or pencil, to write this stuff down on!!

This is how the wiring for a Ford alternator of this era should go. The large black wire (possibly with a stripe) connects to the battery stud (marked BAT), the orange wire with a blue stripe will connect to the field terminal (marked FLD), it is the insulated stud closest to the battery stud and the white wire with a black stripe will connect to the stator terminal (marked STA), it is the only other insulated stud and it is the insulated stud farthest from the battery stud. The customer had not even taken the time to roll the terminal back into the rubber boot.

I connected the wires properly and guess what? It now charges and the charge light goes out. Unbelievable in this day and age a grown man (the customer) cannot connect three wires in the right order to an alternator, even after I told him how and he wrote it down!!!! Maybe I think this stuff is easier (because of my experience) than the rest of the world does, but come on three wires?

This system uses an external regulator. The only reason the regulator (shown below) was not damaged in all of this is that the field wire was actually broken at the terminal and was not making a connection to ground when it was improperly connected.

1997 Jeep Wrangler, Bucks,Cuts Off, Stalls

This 1997 Jeep Wrangler came in with the complaint that the engine would buck, jerk and sometimes stall while driving down the road. The customer also stated that it seemed to happen more on rougher roads. I checked codes and found no codes stored. I also found that the codes had recently been cleared. Time to start inspecting. I saw nothing obvious so I started the engine and commenced to moving the harness around some ( sometimes referred to as a wiggle test). Moving the harness around did duplicate the problem and I isolated the wiring problem down to this particular spot at the rear of the intake manifold.

I disconnected the wiring at all of it’s termination points and lifted it up to see what was going on.

Looking at it as close as I could I thought I saw the problem but was not sure.

I could see the rub and arc marks on the vacuum fitting and the intake fitting boss.

A very close inspection found this and several other bad spots in the harness.

I separated all of the wiring. A little cutting, splicing and taping and I was ready to reassemble.

After the harness was taped back up I installed split loom and loom clamps to finish the job. Looks pretty good, Huh

Another view to show that the harness is repaired protected and positioned away from the metal it originally shorted out on.

1988 Chevrolet C1500 Pickup No Brake, Stop Lights

This 1988 Chevrolet C1500 pickup came in with the complaint that the stoplights or brake lights do not work. The customer had already replaced the stoplight switch, bulbs and fuse. Why he replaced all of that and did not bother checking anything I do not know?? I did check the fuse and it was okay. Time to removed the lower dash cover. Two phillips head screws.

What a rats nest of wiring, but here is the problem. The white wire going into the turn signal switch is broken therefore no brake lights.

I confirmed that there was power coming from the brake light switch to the turn signal switch as shown below.

A clearer picture of the broken wire at the turn signal switch connector.

I replaced the wire and terminal. I had the correct terminal but you could actually jump the wiring around the connectors and just splice into place. I added some length to help prevent a quick failure

Reassembled the connectors and attached to the side of the steering column in it’s hold down bracket.

This is the main reason for the wire failure and my reason for adding extra wire length. The steering column tilt mechanism is very loose and needs to be repaired. I offered but the customer declined repairing at this time.

2003 Ford Expedition, Charge Light On, P0620

This 2003 Ford Expedition came in with the complaint that the alternator had been replaced twice and the charge light light indicator was still coming on. The shop that had installed the alternators had called in desperation as their customer was becoming quite upset. They also stated that the light may stay out all day or only about an hour. When their customer showed up with the vehicle I was a little surprised. The shop usually sends vehicle on a flat bed and drops them off. Time to try and make everybody happy (except Me) while the customer waits(I was trying to eat lunch). I did a quick visual inspection of the wiring at the alternator and everything looked okay. I checked codes and found a code P0620 stored (alternator problem). I then looked at the wiring leading to the alternator and I saw this telltale sign. A wire with discoloration against a metal object.

The metal object in this case was the a/c low pressure or suction line that runs along the lower edge of the battery. I lifted the wiring up and could tell from the amount of discoloration that I might have found the problem.

Yep there’s the problem. I removed some more tape. Wrapped the damaged wire. Rewrapped the harness.

Installed some split loom and cleared the codes. Rechecked the system and all was okay. Back to my lunch.

1995 F150 , High Idle – Code 121

This 1995 Ford F150 pickup came in with the complaint that the idle was very high. The customer stated that the original problem was that the idle was too low and the engine would stall. His neighbor was familiar with Fords and had replaced the IAC valve and now it idles very high. They had disconnected the harness to the IAC valve in order to drive it in. The first thing I did was to plug the harness back into the IAC to see what happens. Idle went very high, close to 2000 rpms. Next I checked codes and found a code 121 stored for a throttle position range fault.

A quick look at data stream and I found the tps voltage at 3.87 volts. Normal on a Ford with a closed throttle is about 1.0 volts. Wide open throttle should be about 4.5 volts so you can see the computer thinks the throttle is much closer to wide open than to closed.

The throttle position sensor is located under the throttle body assembly on this vehicle. It is the part in the following picture with the orange and green wires.

I pulled the connector up to be able to access it and backprobed the orange wire with a sharp pick slid in parallel with the wire through the hole where the wire goes through the seal.

Key on, engine off there was a reading of 5.02 volts. Meaning that the five volt reference voltage to the sensor is okay.

Next I checked the ground in the same manner except that I was checking the black wire. The reading of .024 volts with the other lead connected to battery ground is good. Any reading less that .05 volts is considered okay.

Another way to test the ground is to connect the other lead to battery positive. A reading of a nominal 12 volts would indicate a good ground.

My meter is auto ranging so I do not have to be concerned with polarity while checking voltage. The reversed polarity is indicated by the minus sign to the left of the voltage reading. If your meter is not auto ranging you will need to reverse the leads.

Now on to the tps signal wire. The signal on the green wire is sent to the computer and varies as the throttle is opened and closed.

A voltage of 3.99 volts was found at the tps confirming that the tps is indeed faulty. A normal voltage for a Ford is 1.0 volt at closed throttle.

A diagnosis of a faulty throttle position sensor causing an high idle. The reason the idle would go high in this condition is the program within the computer opens the IAC when the computer sees a signal that the throttle plate is significantly open. This gives a cushion to the system when the throttle is released quickly. Without this cushion the engine would stall.

I have started doing some videos along with my regular posts. I have some refining to do and it will improve with time. To see the part 1 video please click here. To see the part 2 video please click here.

1997 Cadillac Deville, Erratic / High Idle, Code P0507

This 1997 Cadillac Deville came in with the complaint that the idle speed would sometimes be okay but most of the time as the engine warmed up it would get progressively higher and higher until the engine would run at about 3000 rpms on its own with no throttle input. The following picture shows the engine with the Northstar trim panel already removed.

I located the source of the problem to be a large and varying vacuum leak at the backfire pressure release valve located at the end of the intake housing behind the power steering pump.

Since the cover was already removed I did not have to take that off. I started by removing the intake hose from the throttle body. Disconnected the wiring from the throttle body.

Since I wanted to reseal the whole intake anyway I took the mass air flow sensor, the throttle body and the adapter plate loose from the intake.

There were multiple cables, hoses and tubes that had to be disconnected along the way.

Next I had to disconnect the fuel lines. Because this vehicle had been sitting for several hours I did not have to worry too much about relieving the fuel pressure. You may have to and be sure to follow manufacturers procedures for doing so. I do not want you to set your car or yourself on fire!!!!

This is the tool I used to disconnect the fuel lines.

I disconnected the front spark plug wires and folded them to the rear of the engine compartment. Disconnecting the wiring for the fuel injectors and removing the hold down bolts was next.

With everything removed I lifted the intake off and set it on the floor to start removing the backfire valve. The one thing that I wish I would have done is this. Before lifting the intake use a shop vacuum, air hose or visual inspection to make sure there is nothing sitting on the outer edges that could fall inside the engine. When I removed the intake a spotted a metal bushing that supports the engine cover that had fallen down and was sitting on a ledge about to fall into the engine. I had to spend quite a bit of time examining the lower intake port for other debris that may have fallen deeper into the engine. This would have been catastrophic but luckily nothing else did and all was okay. I did however worry about it right up until the time I restarted the engine.

Anyways, now that the intake was off I set it on the floor with the throttle plate area down on a clean rag. The backfire pressure relief valve was pointing straight up and using a pair of needle nose pliers I removed the valve as shown in the next picture. I am sure some one makes a tool for this but the needle nose pliers is all I had to work with on this one. It also took a lot of torque to remove.

A comparison between the new and the old valve.

The back side of the valve. Notice the alignment / locking tabs.

The corresponding alignment slots in the intake.

Drop in the new backfire valve and twist into place using the tool of choice shown earlier.

I installed a new o-ring gasket for the throttle body adapter plate. The manufacturer recommends to replace this gasket anytime the plate is removed and do not lubricate.

I installed new gaskets although technically they can be reused if no damage is seen but really all of this work and the gaskets are 12 years old with 150,000 miles on them. I don’t think so!

The manifold back in place and almost ready to start. Just a few more things and I will be done.

I ran out of pictures because of an unusual occurrence. While installing the fuel rail hold down bolts with spacer tubes one of the plastic tubes shattered and hit me in the forehead. Although I was not badly hurt it did make me lose my concentration on taking more picture for this post. The thing that surprised me most about it was that I was using a torque wrench set to the proper setting and it still broke. After buying a new spacer and trying again I spotted what had happened. the flat washer on the stud / bolt was bowed into a slight cup shape and this shape was throwing the torque of the bolt off and was applying outward pressure to the spacer instead of just downward pressure this made the spacer split and explode. I found one of the pieces fifty feet away from where I was working. So my advise is to check the flat washers to make sure they are flat before starting and replace any that are not.

2003 Cadillac STS Battery Tray Corrosion

This 2003 Cadillac STS came in with battery issues and this is what I found under the back seat where the battery is located. That is a lot of corrosion from a leaking battery. A battery needs to be looked at on a semi regular basis and inspected for corrosion, loose connections, loose mounts and general cleanliness. A dirty battery can actually go dead while not being used because a current path is established through the dirt.

There are a multitude of ways to clean this up and I do not have enough pictures but I can explain my procedure. First I put on a dust mask because the corrosion dust will irritate my sinuses terribly. I then get the shop vacuum, an old screwdriver and a wire brush. I start scraping, chipping and wire brushing the crud while using the shop vac to collect and contain the debris. After I get as much as I think I can get, I take a break, do something else and come back and do it all over again. I will repeat this process three or four times and then I start using a base or alkaline solution, I spray it in and wipe it up what seems like 100 times before there is no more reaction with the battery acid. Then I start rinsing in the same fashion with clean water and a rag. One little thing that I have noticed the coloring in the red shop rags that I use acts just like litmus paper. It turns blue or purple when it comes in contact with battery acid. I do not know if this is by design or just coincidence, just know it happens. After I am satisfied I can do no more good, I let it dry thoroughly and start wire brushing and vacuuming again. Only once or twice now though. Again sorry for the lack of pictures but this is how it looked after cleaning drying and painting the battery area under the seat. Pretty good even if I do say so myself.

After the paint was completely dry I installed a new battery and battery bolts. I wire brushed the battery cable ends with may favorite battery brush tool for side post battery cables. I also treated the battery cables ends with dielectric grease.

The final task was to instruct the customer to return in two weeks for a quick inspection, which went well and then I told her to come back in about three months for another inspection. She did and all is well with this cadillac.

The red wire brush on the end of my 1/4″ cordless impact is my favorite way to clean side post battery terminals and posts. It will work on any 1/4 ” drive tool and can be purchased here.

1999 Chevrolet Lumina Noisy Blower

This 1999 Chevrolet Lumina came in with the complaint that the blower motor is noisy and the air flow from the vents is quite low. I decided to do a video of this repair as I cannot explain the noise that goes along with the complaint and I wanted to try out the new camera and software.

The system will not currently allow me to upload a single video due to the size of the file so I had to do this in two parts. Please let me know if you love or hate the video format as opposed to pictures and text.

The noise is gone and the air flow is restored.

1999 Lexus ES 300, Cooling Fans Stay On

This 1999 Lexus came in with the complaint that the engine cooling fans would stay on even after the key was turned off. The customer stated that they stayed on for an hour or more and she had to disconnect the battery to keep it from going dead. I figure that there was a relay sticking so I took a quick look at a component locator and found that there were several relays listed for the cooling fans. I pulled each one that was listed and no single relay would turn both fans off.

I decided to look at the wiring diagrams and honestly they wire quite confusing because there was actually no way according to just the cooling fan diagrams that the fans could turn off. I dug a little deeper in the diagrams to find out how the listed cooling fan relays were supplied power and ground. In the power distribution diagrams I found that there was an engine main relay listed that had to be the problem. I am pointing to it in the picture below.

I removed the relay and both cooling fans stopped at the same time. I also noticed a slight bit of soot on the white plastic.

I removed the cover from the relay and sure enough the contacts were stuck together and there was a lot of soot.

DSC02561

I tried to break the circuit by applying pressure to the hinge spring but that did not work.

I then used my pocket screwdriver to separate the contacts. I also use the tip of the screwdriver blade to clean the debris from the contact. This enabled the car to be driven again until I could order a new relay from Lexus.

Just a picture of the soot inside the relay cover.

I inserted my pocket screwdriver blade as shown below to release the retaining clips for the cover and repeated on the other side.

A picture of the relay with the cover successfully removed.

This picture show the part numbers on the relay. 85925-17010 and 056700-7770, one number is a Toyota part number and the other is a Denso part number.