May 152016
 

Code C0327 Chevy Suburban 2005Had code C0327 on my 2005 Chevy Suburban 1500 Z71. Replaced Encoder Motor Sensor. Transfer Case shifted and worked just fine for a few days, then quit working. I discovered that I had not secured the wiring harness and the drive shaft wore through a wire to the encoder motor.(green with black stripe) I repaired the wire, but now nothing happens when selecting any of the control panel buttons, none of the lights come on. All the lights will light momentarily when first turning on the key, but that’s it. They don’t light or blink when selected. I have checked all the fuses (at least in the two locations I know of. Under the hood by the battery and the left side of the dash) Did I fry the Encoder Motor Sensor or something else? Is there a voltage check that I can perform to make sure I am getting the voltage to the encoder motor? If so, could you supply me with the pins to check and the voltage to expect and maybe a wiring diagram? Continuity checks? Thanks


RESPONSE

Some customers may comment that the Service 4WD light is on, the 4WD system is inoperative or the 4WD switch indicator lights are blinking.

Code C0327

Technicians may find DTC C0327 in the Transfer Case Control Module (TCCM). This would indicate an encoder sensor malfunction.

It is also possible that the module may be in a mode that will not allow any shifts or updates for the software or calibrations. If this occurs, the TREC fuse (in the engine compartment) must be pulled and reinstalled after 30 seconds. This should allow further operation and service of the system. If a C0550 code is found, this is an unrelated concern and SI diagnostics should be followed for this concern.

The Fix:

I would just reprogram the tccs module if you haven’t already. This should eliminate the problem.

Important: Carefully handle and install the new encoder. Improper installation of the encoder could result in a repeat failure.

  1. Raise the vehicle.
  2. Disconnect the transfer case motor/encoder wiring harness.
  3. Remove the four bolts that secure the motor/encoder to the transfer case.
  4. Remove the motor/encoder from the transfer case.
  5. Remove the black plastic gasket/over plate from the motor/encoder.
  6. Push out the two “single” locking tabs (two lower arrows in illustration above) located on the underside of the housing (motor end).
    6.2. At the other end of the gasket/cover plate, place a flathead screwdriver tip (1) between the gasket/cover plate and the motor housing near the “dual” locking tabs. Twist the screwdriver clockwise/counterclockwise at both sides until the locking tabs break and the gasket/cover plate comes off.
    6.3. Discard the gasket/cover plate.

 

  • Avoiding the wire connection, take two small flathead screwdrivers (one on each side of the encoder) and rock the encoder sensor out using light pressure on each screwdriver.
  • Gently remove the encoder sensor from the wire harness connector. Pry these apart by inserting a small flathead screwdriver between the terminals and the harness connector. Verify that no damage or corrosion exists on either male encoder terminals or female wiring harness terminals.
  • Install the new encoder sensor by connecting to the harness and then gently sliding the encoder sensor over the motor shaft. The hex feature (3) on the encoder should face down toward the motor housing. Make sure the tab (1) on the encoder mates with the notch (2) on the shaft. If the encoder tab is not aligned with the output shaft, rotate the encoder inner ring by hand to mate properly. Press the encoder fully onto the shaft and into the housing.

Important:

Make sure the encoder cover (1) is flush or below the surface of the motor housing and fully seated into place.
Ensure that the new encoder/harness assembly is fully seated to the encoder sensor.

Install a new gasket/cover plate. This should snap into position. Make sure all the four tabs are FULLY engaged.
Install the motor/encoder onto the transfer case using four M8-1.25 X .35 flange head bolts.

Tighten
Tighten all four bolts to 13.5 to 17.6 N·m (10 to 13 lb ft).
Connect the transfer case motor/encoder wiring harness.
Following normal SPS reprogramming procedures, reprogram the transfer case control module with the latest software calibration.
Verify that the 4WD system is operational.

 

May 152016
 

2000 Chevy BlazerI had to change my battery after my blazer sat for a week when i changed it, it will crank but not start


RESPONSE

If it ran just fine before you worked on it, the most likely cause would be something did not get hooked back correctly. Double check your work and insure there is no corrosion on the connections.

You may need to cycle the ignition key on and off to prime the fuel system. Setting for a while may have allowed the fuel pressure to bleed off.

Try spraying some starting fluid in the air filter, if the engine tries to start, you know it is a lack of fuel causing the trouble. If not, it may be electrical.

May 102016
 

1982 Chevy CamaroIs an old school Camaro hard to maintain? Is it easy to improve and does it cost a lot for parts if needed? Also does the number of miles matter? Is it a good car to keep?


RESPONSE

Hard to maintain – No if you are an ASE Certified mechanic with lots of tools and lots of experience with carburetors and oil leaks.

Easy to improve – Sure if you have a pocket full of money that gets refilled often. Cost of parts are relevant to the specific part in which you speak. Oil filters and brake pads are cheap… transmissions and camshafts not so much.  The miles and weather matter most.

good car to keep? If it is an all original Z28 with low miles and perfect body, YES. A plan Jane Camaro with six different body panels and an aftermarket engine and a rigged up stereo system…. No so much.

I would not recommend these years as a collectors vehicle. Something is worth only what someone else is willing to pay for it.

May 092016
 

1998 Chevy Astro Starter ProblemThe battery has a full charge and plenty of gas and it wont start could it be the starter?


RESPONSE

Of course it could be if the engine is not turning over at all. But testing the starting system first may be the best course of action.

  • Check for good battery negative at starter case
  • Have someone hold the ignition key in the “START” position
  • Check for Battery Positive at the “S” terminal on the starter, if seen replace starter. If not seen, check the starter relay and neutral switch. Then trace wiring in the wiring-harness.

1998 Chevy Astro Van Starter Wiring Diagram

1998-chevy-astro-starting-charging-starting-circuit-1-of-1

Starting System Operation

Voltage is applied at all times to the Ignition Switch from Fuse 6 through the RED (242) wire. When the Ignition Switch is turned to the Start position, voltage is then applied to the CRANK fuse through the YEL (5) wire. From the CRANK fuse, voltage is applied to the Park Neutral Position and Backup Lamp Switch through the PPL (806) wire. When the Park Neutral Position and Backup Lamp Switch is placed in Park or Neutral, voltage is then applied to the coil of the Starter Relay through the YEL (1737) wire. Since the Starter Relay is permanently grounded at G104 through the BLK (850) wire, the relay will energize.

Voltage is applied at all times to the  Relay contacts from Fuse 6 through the RED (242) wire. When the Relay energizes, the relay contacts close, and voltage is then applied to the Starter Solenoid. Since the  Solenoid is permanently case grounded, the Solenoid will energize two coils. The Pull-in Winding coil will energize to pull the  Solenoid contacts closed. When the contacts close, a plunger on the contacts will cause the Pull-in Winding coil circuit to open. Then the Hold-in Winding coil will hold the Solenoid contacts closed. Voltage is then applied to the Starter Motor from the Battery through the BLK (1) wire and closed contacts of the  Solenoid. Since the  Motor is also permanently case grounded, the motor will run until the Ignition Switch is moved out of Start position. When this happens, a spring in the  Solenoid will move the  Solenoid contacts and the plunger back to the rest position.

 

 

May 092016
 

2000 Chevy ExpressCheck codes are misfire. cylinders 5 and 7 show solid misfires. changed wires, plugs, fuel pressure reg, and injection spider. still misfires. plugs show good spark. compression good. block check good.


RESPONSE

The Code P0300 means that a cylinder(s) is misfiring or is randomly misfiring. Start by checking for intake leaks, intake gaskets are common caused of multi-cylinder misfiring. If no leak are found the next step is to replace the spark plugs. If the problem persist more tests needs to be done to diagnose problem, see “Possible Causes”.

Possible causes
– Faulty spark plug (s)
– Faulty ignition coil (s)
– Clogged or faulty fuel injector (s)
– Intake air leak
– Fuel injectors harness is open or shorted
– Fuel Injectors circuit poor electrical connection
– Ignition coils harness is open or shorted
– Ignition coils circuit poor electrical connection
– Insufficient cylinders compression
– Incorrect fuel pressure

When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring.

May 062016
 

Started the truck a few weeks ago started fine then the next day went to start it and it was sluggish but when i shut if off it just clicked. So i assumed it was the starter just got the time to swipe it out today approximately three weeks since the starter assumption but after changing same results today all gauges are worming tested the batteries glow plugs are cycling and the indicator light comes one seem i have good voltage but the voltage meter is not showing it and when u start the truck it just clicks with no indication that it will crank at a loss considering it took 4 hours to to get the old starter off in the freezing cold today Really needing some suggestions as we are getting snow and more coming it my winter work vehicle. Thanks in advance for any help or advice someone could lend


RESPONSE

Replace the battery.

 

It takes very little to illuminate lights and activate glow plugs. The starter however requires the most juice to turn over the engine. The battery may read 12 volts setting still without load. When you load test it (draw amperage) the voltage will drop below usable condition.

I use a Battery Load Tester to check my batteries.

Apr 282016
 

2003-chevy-silveradoWhy would my ABS Brake light come on and my speedometer start jumping when I’m in 2wheel drive and hit 30-40mph. And doesn’t do it in 4wheel hi or low?


RESPONSE

The most common reason for the ABS Brake light to come on is when the brake fluid level is low. Since the brake fluid level moves around it may come on while moving up or down hills or on heavy acceleration or deceleration. As for the Speedometer jumping around, it is possibly a VSS- Vehicle Speed Sensor issue or a malfunction in the gauge cluster assembly. Gauge cluster issues are also common on these Chevy trucks

Apr 212016
 

2000 Chevy SilveradoI changed oil pan, timing cover and water pump gaskets on my 2000 Chevy Silverado 1500 2wd 4.3l v6. Leaked oil. it ran fine before I did this and when I got done it would crank but not start. code p0336 came up, changed the crank sensor still no start, did a battery cable relearn and still no start. I did mess up pulling the balancer and pull the rubber about 1/2 inch off on one side, pressed it back on and it looks fine, but could that cause a no start? so far I’ve changed cap , rotor and wires. tried putting old crank sensor back in and still nothing. keeps giving me a p0336 code. wires and plug on sensor look good. had coil and icm tested, they’re good. don’t know what it could be now other than the balancer. any advice?


RESPONSE

I would lean toward the wiring harness, the connection or the signal plate.

Signal Plate

Code P0336

– Crankshaft Position Sensor ‘A’ Circuit Range/Performance

code P0336Possible causes

  • Faulty crankshaft position sensor
  • Crankshaft position sensor wiring harness is open or shorted
  • Crankshaft position sensor circuit poor electrical connection
  • Signal plate may be damaged
  • Starter motor may be faulty
  • Starting system circuit
  • Dead or weak battery

The Crankshaft Position Sensor (CKP) also known as the crank position sensor is an electronic device used in an engine to record the rate at which the crankshaft is spinning. This information is used by the Powertrain Control Module (PCM) to control ignition and fuel injection. The sensor system consists of a rotating part, typically a disc, as well as a static part, the actual sensor.

When the engine is running, the high and low parts of the teeth cause the gap with the sensor to change. The changing gap causes the magnetic field near the sensor to change. The change in the magnetic field cause the voltage from the sensor to change.

Apr 192016
 

2005 Chevy TrailblazerMy 2005 Chevy Trailblazer 2WD won’t accelerate beyond 25-30 mph, transmission fluid was replaced/flushed. I’m taking it to a shop today, any suggestions? thanks


RESPONSE

It can be tough when trying to diagnose your Chevy Trailblazer for lack of acceleration. When it won’t accelerate normally there are a few things that might cause this. If the check engine light is on the first step would be to pull the engine trouble codes. If the engine seems to rev high and your Trailblazer doesn’t want to move at the same time, the most likely reason would be low on transmission fluid. Check the fluid level first. If the level is low, top it off and resume testing. If the transmission fluid level is full, take note to the color. If it is burnt looking or dark, this would indicate burnt internal clutches. Rebuild the transmission to fix it. If the color still looks new, and internal valve body or solenoid issue is most likely the cause.

Apr 182016
 

2004-chevy-silveradoEvery couple of days if i let my 2004 Chevy Silverado 1500 sit the battery drains. I have to jump it to start it but every time I take it and have it tested they can never find anything wrong. Battery cables are good and tight and have changed the battery and alternator and shut off the interior lights to where they don’t come on is there anything else i should be looking at


RESPONSE

Glove box bulb is one place to look. Wait till night time and then look as it will be easier to see a light. Also check for loose change in the cigar lighter and power ports. A dime or gum wrapper is all it takes to get lodged in there and it will drain the battery.

You may disconnect the battery and see if the battery is still dead after it sits. In most cases the battery itself is the problem. It may test OK at the local parts house, but I can assure you the test is not that accurate.

If you still are having issues at this point you may has a parasitic draw.

Wiki has done a great job on explaining how to test for a parasitic battery draw.