2000 Chevrolet Impala, No Crank Condition

This 2000 Chevrolet Impala came in with several complaints. The main complaint was that the engine would not crank over or run. Also the ABS lights would come on. The problem according to the customer had been intermittent and going on for about a year. Luckily, when the vehicle arrived the problem was still present. The first thing that I did was connect my Tech 2 to the dlc and check for codes and data. Just my luck, no communication. There were however multiple abs codes for the rear sensors.

Well, where to start on this one. I knew the first thing that I should do was to check the fuses but, when I opened the hood, I decided to look around the computer area. The computer is located in the air filter assembly.

One of the first things that I spotted was this gray in line harness connector. I realized that some of the wiring went to the engine control computer.  I also thought that some one might have unplugged it to change the air filter or get to the computer. So, what the heck. Let me see if it is fully seated. CLICK!!! No, I couldn’t be that lucky.

Well, I was that lucky. Data stream was back and the engine fired right up.

I took the connector back apart and checked for any signs of arc damage. The connector looked fine.

I cleared all of the codes out of the vehicle computers and test drove the car. No Service Engine Soon light or ABS lights. This poor customer and multiple other mechanics had been fighting this problem off and on,  for about a year. Just goes to prove the old saying true, ” I’d rather be lucky than good sometimes”.  I also proves that the KISS diagnostic theory is best. KISS = Keep It Simple Stupid

1994 Dodge Pickup, No Charge Condition

This 1994 full sized Dodge pickup came in with a complaint of the battery going dead. A quick check showed a no charge condition. With the engine running, I checked for power on the main alternator power lead. Next I checked for power going to the field terminals. The inside one had power but the outer terminal did not, as shown in the picture below. Diagnosis of an open field circuit within the alternator. Most likely worn brushes.

Time to disconnect then battery. Then, I loosened and removed the belt from the alternator.

Loosened and removed the upper and lower mounting bolts. Rolled the alternator slightly forward to  disconnect all wiring connections.

After sliding the alternator off of the lower mount, I rolled the alternator slightly forward to  disconnect all wiring connections. Next, I started rotating the alternator ccw around the dipstick tube.

I continued rotating the alternator around the tube and under the a/c lines.

After repairing the alternator, I tested the field circuits again. To view the repair of this alternator please click here. This time I had a flickering light on the outer field terminal. Sorry you can’t see the flickering in a still shot.

You can however see that the charging system is now working.

Changing Brushes in a Denso Alternator

To check and change the brush holder assembly on a Denso internal fan alternator, start by removing the nut on the insulator post. Then with the insulator removed proceed to removing the remaining nuts, one screw and ground strap. The extra screw and ground strap will not always be present. Note that this particular alternator is off of a Chrysler, Dodge, Jeep or Plymouth vehicle and does not have a built in voltage regulator. Most Denso alternator of this style do have a built in voltage regulator and there will be a round, oval or T shaped socket for a harness to plug into. The brush holder replacement procedure is the same except that this particular brush holder uses three attaching screws where all others only use two.

Using a screw driver or other device, lift the tin cover from the back of the alternator assembly. This will expose the brush holder along with the rectifier and regulator if equipped.

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Remove the screws that hold the brush holder in place. Most of these alternators only have two screws. However this one uses three. Some times these screws can be difficult to loosen and the screws can easily be damaged. Make sure you use a good #2 phillips head screw driver and use a firm grip.

In the picture below you can clearly see the worn brushes. I am holding it it upside down to show the more worn brush.

Inspect the slip ring for excessive wear. The copper slip rings can be worn so thin that the plastic underneath will be exposed. If this happens you may want to consider a replacement alternator. Oil on the brushes or slip rings will rapidly accelerate slip ring wear. So please make sure all oil leaks are repaired. If you have an ohmmeter it would be advisable to check the resistance across the two slip rings and compare it to factory specifications. In most cases it will be between 2 and 3 ohms.

The new brush holder ready to install.

Using a small screwdriver push the brushes back into the brush holder and slide the assembly into place.

Start on screw and then wiggle the brush holder as needed to line up the remaining holes.

Install the remaining screws and tighten the brush holder assembly down.

Install the rear cover and the repair is done. If possible test the alternator before reinstalling it.

Need to order a brush holder for your Denso alternator, click here.

1999 Chevrolet Suburban, Erratic Speedometer Caused by Burnt Battery Terminal

This 1999 Chevrolet Suburban came in with the complaint of an erratic speedometer. I have seen this problem before, so I went straight to the positive battery cable connections. This is what I found. At first the cables look a little corroded but not too bad.

A closer look shows heavy corrosion on the terminal along with heat damage to the red protective terminal boot.

The battery terminal with the molded boot looked pretty bad from the underside.

I removed the lead spacer from the battery terminal. I did have to use a pair of pliers to remove it.

Then a razor blade to remove the rubber ring portion of the red boot.

Normally, a little clean up and a new boot, that will slide over the remaining red rubber is all that is needed. However this terminal was badly damaged.

I cut off the old terminal. Stripped and cleaned the inner cable core with a wire brush. Used my pliers to fold over the tabs on the new terminal. A little work to make sure the connection was clean and tight. Although I do not own a factory crimping tool for this step, I have never had a problem doing it this way.

I heated and soldered the crimp connection to seal the already good mechanical crimp. In case you did not know it, solder by itself makes a fairly lousy connection. Its job is to seal and strengthen, an already good mechanical connection.

After the soldering job was complete and cooled down, I folded over the tabs for the insulation. Those tabs are there for strain relief.

A new bolt, lead spacer, dielectric grease and protective red boot and this one was done. To order battery bolts and spacers, please click here.

It was very surprising to me that the customer never had a problem, with cranking this vehicle. This business is full of strange things though. I guess that is what makes it interesting to me.

1995 Toyota Camry, No Tail or Stop Lights

This 1995 Toyota Camry came in with the complaint that the tail lights do not work. I have fixed many of these over the years. Sometimes it is the tail lights and some times the problem is the stoplights do not work. You can see in the picture below that the small marker light is working but not the main tail light bulb.

To remove the light assembly there are two 8 mm nuts on the inside of the trunk that have to be removed. The trunk liner has to be pulled loose to gain access to the nuts.

In the next picture I am trying to show that there are three wires and the bulb has only one element. You may need to double click on the picture to enlarge it.

The bulb on the left is the one that was installed in the socket when I removed it. The one on the right is the correct bulb.

The socket has two terminals inside the hole.

That was the cause of the problem, now for the fix. The bulb failure module is behind a bracket on the left side of the trunk. The picture below shows it after it has been released from its mounting position.

The tabs have to be pushed in and then the module can be pulled from the bracket.

Once the module is out and the cover has been removed, the circuit board can be inspected for damage. I am pointing to the melted solder in the next picture. Again you can double click on these pictures to enlarge them.

The back side of the board where the heat damage is more evident. Hard to see though because of the flash glare.

The resoldered joints at the lower center of the picture. I reassembled the lights with the correct bulbs installed. Put the module back together and all was well again.

2002 Dodge Neon, Speedometer Not Working

This 2002 Dodge Neon came in with the complaint that the speedometer was not working. To test the cluster press in the trip reset button, turn the ignition switch on and release the reset button. The gauges will move in increments and the dash warning lights will come on with the exception of the turn signal, high beam and foglight indicators. All systems worked on this vehicle except for the speedometer. Diagnosis of a faulty instrument cluster. The customer did not want to spring for a new cluster and asked if I would look into what might be wrong internally.

To remove the instrument cluster, the trim panels for the front “A” pillars have to be removed. They unsnap and pull out.

The under dash trim panel needs to be removed. I think it just unsnaps, I can’t remember if there are screws or not, so be careful. Also there is a screw at each end of the dash cover that needs to be removed, Phillips head.

Then the dash top can be unsnapped as well. I forgot to get a picture of removing the lower instrument trim panel. It is the curved piece just below my hand in the picture below. I don’t remember if there are any screws for the panel under the steering column hidden behind this panel or not.

With the upper cover loosened the cluster can be removed. To make it easier you can also remove the passenger side “A” pillar trim panel as well.

There are two upper screws and two lower screws. All phillips head.

Lift the dash cover up and rotate the cluster out as shown below

Slide it out the driver’s side of the dash. The customer did not want to spring for a new cluster and asked if I would look into what might be wrong internally. So I did.

Took the cluster to a work bench and removed the screws that hold the cardboard backer panel in place.

Lifted the cardboard panel off and set it aside.

Next removed the screws that held the circuit board in place.

Carefully unplugged the wiring harness connector as shown in the picture below.

What I found in my investigation is that the solder joints at the resistor that I point to in the following pictures, weakened with age.

With all of the screws removed, I lifted the circuit board from the rear of the instrument cluster. You will need to lift and rock the panel, a little at a time, to get it to release from the gauge pins.

With the panel released you can flip it over and see the other side of the resistor terminals, as shown in the pictures below.

I carefully resoldered the weak joints and reassembled the dash. Just to be sure I soldered the terminals on both sides of the board. I did the self test and all tested well. Then I took the car down the road to ensure everything worked okay and it did.

2002 GMC Sierra, Installing a Fused Battery Lead

This 2002 GMC Sierra came in with charging system complaints that I showed the repair for in an earlier post. Now I want to show how the whole situation could have been avoided if the installer had followed simple instructions. To see that repair please click here. If you recall the owner had installed electric cooling fans and removed the mechanical fan assembly.

Improper wiring had lead to melting of the positive battery cable junction block.

It is very easy to wire in extra circuits on later model Chevrolet and GMC trucks and SUV’s. Start by removing the corner bracket.

This will allow you to lift the cover from the underhood fuse box.

With the cover removed you will find studs with nothing attached to them and empty Maxi fuse holders.

There will be information about these circuits on the inside of the fuse box cover.

You can see I installed a 40 amp Maxi fuse (orange) and at the bottom left you can see the wire that I attached with a ring terminal and heat shrink tubing (red wire). If you look up towards the center of the fuse box you will see where the installer had just jabbed a wire in under a fuse. This is just trouble waiting to happen.

I have to get a picture of a great fuse tap that allows one to add a circuit with ease and it will not damage the fuse box. To find fuses and fuse holders please click here.

2002 GMC Sierra, Erratic Charging Condition, Battery Goes Dead

This 2002 GMC Sierra came in with the complaint that the battery had gone dead and that the voltmeter was reading low voltage at times. I opened the hood and the problem was quite evident to me but I decided to do some testing anyways. The following picture shows 14.32 volts at the alternator output stud. Engine running of course.

This is the obvious problem. A poor connection at the positive battery cable jump point.

Someone had wired in an electric cooling fan system and taken the mechanical fan assembly off.

While testing, I decided to check the temperature of the connection. The connection, as you can see was at 289 degrees F. The vehicle had only been running about 2 to 4 minutes at this time.

The voltage was only 9.98 volts.

The stud had melted loose of the insulating block assembly.

And there is the actual reason for all of this mess. Bare wire twisted around the stud with no terminal. On top of that the curve of the wire is even wrong for household wiring. See how the wire is hooked CCW. At bare minimum it should have been on there in a CW direction so that the loop would have tightened as the nut wast tightened. Didn’t we all learn that in high school electricity / science classes.

The plastic in the insulating block was badly melted however the cable eye terminal was just a little dirty.

A quick cleaning and it was good as new.

I checked locally, the fusible link from the alternator and the insulating block both had to be ordered. So I continued cleaning up the mess.

There sure has been a lot of heat on that stud. At least 289 degrees F, right.

I surely do love having a glass bead cabinet. I cleaned and tightened all of the connectors and epoxied the insulating block. The system is now operating properly and I will install the new parts when they arrive.

To see how to properly install a fused circuit on this and similar trucks please click here.

2003 Chevrolet Silverado, A/C Leaks

This 2003 Chevrolet Silverado had come in about a month earlier, on a Friday afternoon and the customer wanted the system cold for a trip he was going on. The system had a low refrigerant charge. I added dye and oil, vacuumed it down and recharged the system. I advised the customer to come back after his trip and he did a month later:) Anyway it was very easy to see where the leak was at. I had suspected the area due to oil and dirt build up, but he did not have time to fix it the first time around. You can clearly see the dye in the picture below.

It was a simple matter of recovering the system. Removing the attaching nut. Cleaning up the dirt and oil residue.

Pulling the connector apart and removing the sealing washer.

I grabbed a new sealing washer from my o-ring kit.

Installed the new washer.

Reconnected the fitting.

The high side service valve had also been leaking. The cap hissed when I removed it and there was dye in the hole and weeping down the inside edge of the cap.

The valve assembly unscrews from the line. There is a hex on the line fitting to hold with a wrench, while turning the fitting with the appropriate tool. I use smooth jaw, slip joint pliers.

I vacuumed the system down and recharged it and all was good again. I did clean the debris from the condenser fins and radiator with shop air, while the system was vacuuming.

2001 Pontiac Grand Am, Battery Goes Dead, Key Will Not Turn Off

This 2001 Pontiac Grand Am came in with the complaint that the battery would go dead overnight. Well no surprise, basic inspection found that the warning lights on the left side of the instrument cluster stayed on even with the key off.

Further inspection found that the key was not turning all of the way off. The key is actually positioned between the off and accessory positions. The key did come out, even though it is not supposed to, but that is another story altogether.

I did a lot more checking, including reattaching some linkage that had come loose somehow. The other things that I had found wrong were merely symptomatic of someone else’s efforts to repair the condition. The original problem is shown below the push button was remaining stuck in even though the shifter was fully in the park position. I could wiggle it out and the key would turn all of the way off and the dash warning lights would go out.

The actual problem, dried syrup from spilled sodas. People and their nasty @$$&% cars. A good cleaning and all was well again.