Circuit Testing Procedures - Non-Dtc-Based Diagnostics: Diagnosis Dodge Dart PF

TROUBLESHOOTING TOOLS

When diagnosing a problem in an electrical circuit there are several common tools necessary. These tools are listed and explained below

Voltmeter

The voltmeter is used to measure the electrical pressure or the voltage difference between two points. A voltmeter reads available voltages such as battery voltage, generator output voltage, and voltage drop across a component or conductor. A high voltage drop may indicate a high resistance in the circuit. The voltmeter can be used to locate an open circuit and circuits with an unintentional ground. Observing polarity, always connect a voltmeter in parallel to the existing circuit. If the leads are reversed on a digital multimeter, a minus sign appears in the display.

Ohmmeter

The ohmmeter is used to measure the resistance of a component or the resistance between two points in a circuit in ohms, and to check a portion of the circuit for continuity. Some meters have a built-in tone to indicate that the circuit has continuity. No resistance indicates a short circuit or unintentional ground whereas resistance that is higher than specification indicates a high resistance in the circuit such as a loose, dirty or corroded connection, or a defective component. An "OL" reading means that the circuit or component had infinite resistance; an open circuit or defective component is indicated. Ohmmeters have an internal battery and must never be connected to a power circuit. Connecting an ohmmeter to a powered circuit causes the meter fuse to blow and can damage its dry cell battery. Ohmmeters can be connected into a circuit without regard to polarity, unless the circuit contains a diode. When using an ohmmeter, the component or portion of the circuit must be isolated from other components or branches to avoid false readings.

Ammeter

Amperage or current is the measure of the rate of electron "flow" in a circuit. It is measured in the unit of the Ampere, simply called an Amp (A). In order to measure current in a circuit, the circuit must be broken or opened, and an ammeter must be inserted in series (in-line) with the circuit so that all the current that flows through the circuit will have to go through the meter. When measuring current in this manner, it requires the meter be made part of the circuit, this type of measurement is more difficult than measuring either voltage or resistance.

When an ammeter is placed in series with a circuit, it ideally drops no voltage as current goes through it. In other words, it acts very much like a piece of wire, with very little resistance from one test probe to the other. Consequently, an ammeter will act as a short circuit if placed in parallel (across the terminals of) a substantial source of voltage. If this is done, a surge in current will result, potentially damaging the meter. Ammeters are generally protected from excessive current by means of a small fuse located inside the meter housing. If the ammeter is accidently connected across a substantial voltage source, the resultant surge in current will "blow" the fuse and render the meter incapable of measuring current until the fuse is replaced.

Consult the owner's manual of the particular model of meter you own for details on measuring current.

12-Volt Test Light

The 12-Volt test light when properly used, is one of the best and quickest pieces of test equipment available for troubleshooting 12-volt power systems. It's especially good for times when there are only two voltages, battery voltage and no voltage. For example, if you're checking to see if you have 12-volts on the Battery(+), the test light will immediately tell you if voltage is present or not.

With any test equipment, you should confirm that it's in good working order before you begin testing. For a test light, you have to have a voltage source. Connect the test light's ground clip to a good ground and touch it to a point where you believe that there is 12-volt supply. If the light doesn't light up, check the light by connecting it directly across the battery. Initially, make sure that you have the ground clip on the negative battery terminal. If you touch the probe to the positive terminal, the test light should light up. If it doesn't and the battery is not completely dead, the test light isn't working properly. The test light must be in proper working order before any circuit testing can occur.

Jumper Wire

The sole purpose of the jumper wire is to complete a circuit. It is nothing more than a suitable length of insulated wire with terminals or connectors on each end. Jumper wires may be bought or made with various sizes of wire and styles of terminals including alligator clips, spade lugs and pin plugs, and should include a fuse device of some type for circuit and component protection. A jumper wire is used to verify a faulty conductor by substituting a known good one. It is jumped across a suspicious conductor in the circuit. If the circuit works with the jumper, but not without, there is an open somewhere in the area being jumped. A jumper wire is ONLY used to bypass a faulty conductor (including switches and connectors). NEVER bypass a load device with a jumper wire. The circuit needs the resistance from the load device and shorting across it causes high current flow, which could damage other components.

Scheme 13

Probing Tools

These tools are used for probing terminals in connectors. Select the proper size tool from Special Tool Package (special tool #6807, Terminal Tools), and insert the probing end (2) into the terminal being tested. Use the other end of the tool (1) to insert the meter probe.

TROUBLESHOOTING WIRING PROBLEMS

When troubleshooting wiring problems there are six steps which can aid in the procedure. The steps are listed and explained below. Always check for non-factory items added to the vehicle before doing any diagnosis. If the vehicle is equipped with these items, disconnect them to verify these add-on items are not the cause of the problem.

Perform the following Six Step Diagnosis Process

1. Verify the problem.
2. Verify any related symptoms. Do this by performing operational checks on components that are in the same circuit. Refer to «SYSTEM WIRING DIAGRAMS»(ref-607579) .
3. Analyze the symptoms. Use the wiring diagrams to determine what the circuit is doing, where the problem most likely is occurring and where the diagnosis will continue.
4. Isolate the problem area.
5. Repair the problem area.
6. Verify the proper operation. For this step, check for proper operation of all items on the repaired circuit. Refer to «SYSTEM WIRING DIAGRAMS»(ref-607579) .

Note. The Six Step Diagnosis Process used by Chrysler is a time proven process. The basic concepts of this process have been used by others for problem solving for many years. The successful application of this process requires a solid understanding of the conditions that affect each step, and when its time to advance to the next step. These conditions based on experience formulate what is known as "Best Practices".

Scheme 14

The purpose of the following procedure(s) is to demonstrate how to check the voltage of a 12-volt fused battery B(+) circuit with a test light or voltmeter.

Note. The circuit shown is an example, and is intended for demonstrational purpose only.

The following are circuit tests covered in this procedure

1. Testing 12-Volt Fused Battery B(+) Circuit Voltage With A Test Light
2. Testing 12-Volt Fused Battery B(+) Circuit Voltage With A Voltmeter

Note. Perform the following test using a known good test light or functioning multimeter.

Below is a list of possible causes that could be related to a No Voltage condition.

Scheme 15

Scheme 16

1. TESTING 12-VOLT FUSED BATTERY B(+) CIRCUIT VOLTAGE WITH A TEST LIGHT NOTE: Before testing any circuits, first verify the 12-volt test light is operating properly. Connect the 12-volt test light to battery ground or to any other known good ground. Touch the lead of the test light to Battery(+). If the test light is operational, it should illuminate brightly. Turn the ignition off. Disconnect the wire harness connector from the component that is being tested. NOTE: Check connectors - Clean/repair as necessary. At this time, leave all in-line connectors connected. Connect the 12-volt test light to a known good ground. Use the test light lead to carefully probe the Battery or Ignition voltage circuit in the harness connector. First check with the ignition off, next check with the ignition on, and lastly check while cranking the engine. Does the test light illuminate brightly? Yes The circuit is not open at this time or the condition that originally caused the open may not be present at this time. Continue to monitor the test light and wiggle the wire harness and connectors to check for an intermittent open or excessive resistance condition. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the open could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply. No Repair the open in the circuit. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors where the open could occur. One method to help isolate the open is to disconnect any in-line connectors and measure the resistance from one side of the in-line connector to the matching component harness connector. If the open goes away, the open is on the other side of the in-line connector. If this is a fused circuit, make sure to inspect the fuse. If the fuse is open, check the circuit for a short to ground before installing a new fuse. The circuit may have a short to ground causing the fuse to open. This short to ground could be in the wire harness or in one of the components the circuit is supplying voltage to.
2. TESTING 12-VOLT FUSED BATTERY B(+) CIRCUIT VOLTAGE WITH A VOLTMETER NOTE: The connector displayed in the graphics are only an example. Turn the ignition off. Disconnect the wire harness connector from the component that is being tested. NOTE: Check connectors - Clean/repair as necessary. At this time leave all in-line connectors connected. Use a multimeter set to measure DC voltage. Connect the ground lead of the meter to a known good ground. Use the positive lead of the multimeter and probe the circuit that is being checked for voltage. Ignition on, engine not running. Is the voltage within specifications for this circuit? Yes The circuit is functioning properly or the condition that originally caused the open or short may not be present at this time. Continue to measure the voltage and wiggle the wire harness and connectors while checking for an intermittent open or short. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply. No Repair the open or short to ground in the circuit. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur. One method to help isolate the open or short is to disconnect any in-line connectors that the circuit being checked runs through and check for the voltage again. If the voltage is present, the open or short is on the other side of the in-line connector.

Scheme 17

The purpose of the following procedure is to demonstrate how to check the voltage of a 12-Volt switched battery B(+) circuit with a test light or voltmeter.

Note. The circuit shown is an example, and is intended for demonstrational purpose only.

The following are circuit tests covered in this procedure

1. Testing 12-Volt Switched Battery B(+) Circuit Voltage With A Test Light
2. Testing 12-Volt Switched Battery B(+) Circuit Voltage With A Voltmeter

Note. Perform the following test using a known good test light or functioning multimeter.

Below is a list of possible causes that could be related to a No Voltage condition.

Scheme 18

Scheme 19

1. TESTING 12-VOLT SWITCHED BATTERY B(+) CIRCUIT VOLTAGE WITH A TEST LIGHT NOTE: Before testing any circuits, first verify the 12-volt test light is operating properly. Connect the 12-volt test light to battery ground or to any other known good ground. Touch the lead of the test light to Battery(+). If the test light is operational, it should illuminate brightly. Turn the ignition off. Disconnect the wire harness connector from the component that is being tested. NOTE: Check connectors - Clean/repair as necessary. At this time, leave all in-line connectors connected. Connect the 12-volt test light to a known good ground. Use the test light lead to carefully probe the Battery or Ignition voltage circuit in the harness connector. First check with the ignition off, next check with the ignition on, and lastly check while cranking the engine. Does the test light illuminate brightly? Yes The circuit is not open at this time or the condition that originally caused the open may not be present at this time. Continue to monitor the test light and wiggle the wire harness and connectors to check for an intermittent open or excessive resistance condition. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the open could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply. No Repair the open in the circuit. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors where the open could occur. One method to help isolate the open is to disconnect any in-line connectors and measure the resistance from one side of the in-line connector to the matching component harness connector. If the open goes away, the open is on the other side of the in-line connector. If this is a fused circuit, make sure to inspect the fuse. If the fuse is open, check the circuit for a short to ground before installing a new fuse. The circuit may have a short to ground causing the fuse to open. This short to ground could be in the wire harness or in one of the components the circuit is supplying voltage to.
2. TESTING 12-VOLT SWITCHED BATTERY B(+) CIRCUIT VOLTAGE WITH A VOLTMETER NOTE: The connector displayed in the graphics are only an example. Turn the ignition off. Disconnect the wire harness connector from the component that is being tested. NOTE: Check connectors - Clean/repair as necessary. At this time leave all in-line connectors connected. Use a multimeter set to measure DC voltage. Connect the ground lead of the meter to a known good ground. Use the positive lead of the multimeter and probe the circuit that is being checked for voltage. Ignition on, engine not running. Is the voltage within specifications for this circuit? Yes The circuit is functioning properly or the condition that originally caused the open or short may not be present at this time. Continue to measure the voltage and wiggle the wire harness and connectors while checking for an intermittent open or short. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply. No Repair the open or short to ground in the circuit. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur. One method to help isolate the open or short is to disconnect any in-line connectors that the circuit being checked runs through and check for the voltage again. If the voltage is present, the open or short is on the other side of the in-line connector.

Scheme 20

The purpose of the following procedure is to demonstrate how to check the voltage of a 5-Volt supply circuit with a voltmeter.

Note. The circuit shown is an example, and is intended for demonstrational purpose only.

The following are circuit tests covered in this procedure

1. Testing A 5-Volt Supply Circuit For Voltage
2. Testing A 5-Volt Supply Circuit And Sensor Ground Circuit

Note. Perform the following test using a known good multimeter.

Below is a list of possible causes that could be related to a No Voltage condition.

Scheme 21

Scheme 22

1. TESTING A 5-VOLT SUPPLY CIRCUIT FOR VOLTAGE Turn the ignition off. Disconnect the sensor harness connector. NOTE: Check connectors - Clean/repair as necessary. Turn the ignition on. Set the multimeter to measure DC voltage. Connect the negative lead of the multimeter to a known good ground. With the positive lead of the multimeter, carefully probe the 5-volt supply circuit. Is the voltage between 4.7 and 5.2 volts? Yes Go To 2 No Check the 5-volt supply circuit for an open or short to ground. For further assistance, perform the appropriate Sensor Reference Voltage DTC diagnostic procedure.
2. TESTING A 5-VOLT SUPPLY CIRCUIT AND SENSOR GROUND CIRCUIT With the multimeter set to measure DC voltage. Move the negative lead of the multimeter to carefully probe the sensor ground or sensor return circuit in the harness connector. With the positive lead of the multimeter, carefully probe the 5-volt supply circuit. Is the voltage between 4.7 and 5.2 volts? Yes At this time the 5-volt supply and sensor ground circuit are working properly. Continue to measure the voltage between the wires, wiggle the wire harness and connectors while checking for an intermittent condition. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the open could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply. No Repair the open or excessive resistance in the Sensor Ground (Sensor Return) circuit.

Scheme 23

The purpose of the following procedure is to demonstrate how to check a circuit for a Short to Ground.

Note. The circuit shown is an example, and is intended for demonstrational purpose only.

The following are circuit tests covered in this procedure

1. Testing For A Short To Ground Using An Ohmmeter

Note. Perform the following test using a known good multimeter.

Below is a list of possible causes that could be related to a Short to Ground condition.

DIAGNOSTIC TEST

TESTING FOR A SHORT TO GROUND USING AN OHMMETER

Scheme 24

Note. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the multimeter. Take this value and subtract it from the value recorded when measuring the resistance of the circuit being checked (The meter leads can add 0.5 ohm or more of total resistance).

1. Turn the ignition off.
2. Disconnect the wire harness connectors from the module and component for the suspected circuit being shorted to ground. NOTE: Check connectors - Clean/repair as necessary.
3. With the component wire harness connectors disconnected, use a meter set to measure Ohms (ohms), and measure the resistance between the circuit and a known good ground.
4. Use the negative lead of the meter and touch a known good ground.
5. Use the positive lead of the meter and carefully probe the circuit suspected of having the short. Is the resistance to ground below 10k ohms ? Yes Repair the short to ground. Use the wiring diagram as a guide to follow the path of the circuit. One method to help isolate the short is to disconnect any in-line connectors that the circuit being tested runs through and measure for the short again. If the short goes away, the short is on the other side of the in-line connector. No The circuit is not shorted to ground or the condition that originally caused the short may not be present at this time. Continue to measure the resistance, wiggle the wire harness and connectors while checking for an intermittent short. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply.

Scheme 25

The purpose of the following procedure is to demonstrate different methods of checking for a short to voltage in a circuit. When diagnosing a DTC it might be necessary to verify that proper voltage is on a circuit or that a circuit is not shorted high.

Note. The circuit shown is an example, and is intended for demonstrational purpose only.

The following are circuit tests covered in this procedure

1. Testing For A Short To Battery Voltage Using A Voltmeter
2. Testing For A Short To Switched Battery Voltage Using A Voltmeter
3. Testing For A Short To Battery Voltage Using A 12-Volt Test Light
4. Testing For A Short To Switched Battery Voltage Using A 12-Volt Test Light

Note. Perform the following test using a known good test light or functioning multimeter.

Below is a list of possible causes that could be related to a Short To Voltage condition.

Scheme 26

Scheme 27

Scheme 28

Scheme 29

1. TESTING FOR A SHORT TO BATTERY VOLTAGE USING A TEST LIGHT NOTE: Before testing any circuits, first verify the 12-volt test light is operating properly. Connect the 12-volt test light to battery ground or to any other known good ground. Touch the lead of the test light to Battery(+). If the test light is operational, it should illuminate brightly. Turn the ignition off. Disconnect the wire harness connectors of all components that contain the circuits that are suspected of having the short. NOTE: Check connectors - Clean/repair as necessary. At this time leave all in-line connectors connected. Connect the 12-volt test light to a known good ground. Use the lead of the test light and carefully probe the circuit suspected of having the short. WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury. First, check with the ignition off, next with the ignition on, and lastly while cranking the engine. Does the test light illuminate brightly? Yes Repair the short to voltage. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur. One method to help isolate the short is to disconnect any in-line connectors that the circuit being checked runs through and check for the short again. If the short goes away, the short is on the other side of the in-line connector. No The circuit is not shorted to voltage or the condition that originally caused the short may not be present at this time. Continue to measure the resistance and wiggle the wire harness to check for an intermittent short. NOTE: By disconnecting the wire harness connectors you may have eliminated the source of the voltage causing the short. Use the wiring diagram as a guide, check to see if there are any battery circuits in the same wire harness as the circuit you are testing. It is necessary to check for a short to those circuits using an ohmmeter. Refer to «STANDARD PROCEDURE»(ref-646331-S04956210322014072800000) and perform the Check for a Short Between Multiple Circuits diagnostic procedure. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related component and wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply.
2. TESTING FOR A SHORT TO SWITCHED IGNITION VOLTAGE USING A TEST LIGHT NOTE: Before testing any circuits, first verify the 12-volt test light is operating properly. Connect the 12-volt test light to battery ground or to any other known good ground. Touch the lead of the test light to Battery(+). If the test light is operational, it should illuminate brightly. Turn the ignition off. Disconnect the wire harness connectors of all components that contain the circuits that are suspected of having the short. NOTE: Check connectors - Clean/repair as necessary. At this time leave all in-line connectors connected. Connect the 12-volt test light to a known good ground. Use the lead of the test light and carefully probe the circuit suspected of having the short. WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury. First, check with the ignition off, next with the ignition on, and lastly while cranking the engine. Does the test light illuminate brightly? Yes Repair the short to voltage. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur. One method to help isolate the short is to disconnect any in-line connectors that the circuit being checked runs through and check for the short again. If the short goes away, the short is on the other side of the in-line connector. No The circuit is not shorted to voltage or the condition that originally caused the short may not be present at this time. Continue to measure the resistance and wiggle the wire harness to check for an intermittent short. NOTE: By disconnecting the wire harness connectors you may have eliminated the source of the voltage causing the short. Use the wiring diagram as a guide, check to see if there are any battery circuits in the same wire harness as the circuit you are testing. It is necessary to check for a short to those circuits using an ohmmeter. Refer to «STANDARD PROCEDURE»(ref-646331-S04956210322014072800000) and perform the Check for a Short Between Multiple Circuits diagnostic procedure. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related component and wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply.
3. TESTING FOR A SHORT TO BATTERY VOLTAGE USING A VOLTMETER Turn the ignition off. Disconnect the wire harness connectors of the components that contain the circuit that is suspected as having a short. NOTE: Check connectors - Clean/repair as necessary. At this time leave all in-line connectors connected. With all the component wire harness connectors disconnected, use a multimeter set to measure DC voltage. Connect the ground lead of the meter to a known good ground. Use the positive lead of the multimeter and probe the circuit that is being checked for a short. Is there any voltage present? Yes Repair the short to battery voltage. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur. One method to help isolate the short is to disconnect any in-line connectors that the circuit being checked runs through and measure for the short again. If the short goes away, the short is on the other side of the in-line connector. No The circuit is not shorted to voltage or the condition that originally caused the short may not be present at this time. Continue to measure the voltage and wiggle the wire harness to check for an intermittent short. NOTE: By disconnecting the wire harness connectors you may have eliminated the source of the voltage causing the short. Use the wiring diagram as a guide, check to see if there are any battery circuits in the same wire harness as the circuit you are testing. It is necessary to check for a short to those circuits using an ohmmeter. Refer to «STANDARD PROCEDURE»(ref-646331-S04956210322014072800000) and perform the Check for a Short Between Multiple Circuits diagnostic procedure. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply.
4. TESTING FOR A SHORT TO SWITCHED IGNITION VOLTAGE USING A VOLTMETER Turn the ignition off. Disconnect the wire harness connectors of all components that contain the circuits that are suspected as being shorted. NOTE: Check connectors - Clean/repair as necessary. At this time leave all in-line connectors connected. With all the component wire harness connectors disconnected, use a multimeter set to measure DC voltage. Connect the ground lead of the meter to a known good ground. Use the positive lead of the multimeter and probe the circuit suspected of having the short. Ignition on, engine not running. Is any voltage present? Yes Repair the short to ignition voltage. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur. One method to help isolate the short is to disconnect any in-line connectors that the circuit being checked runs through and check for the short again. If the short goes away, the short is on the other side of the in-line connector. No The circuit is not shorted to voltage or the condition that originally caused the short may not be present at this time. Continue to measure the voltage and wiggle the wire harness to check for an intermittent short. NOTE: By disconnecting the wire harness connectors you may have eliminated the source of the voltage causing the short. Use the wiring diagram as a guide, check to see if there are any battery circuits in the same wire harness as the circuit you are testing. It is necessary to check for a short to those circuits using an ohmmeter. Refer to «STANDARD PROCEDURE»(ref-646331-S04956210322014072800000) and perform the Check for a Short Between Multiple Circuits diagnostic procedure. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply.

TESTING GROUND CIRCUIT WITH TEST LIGHT

Scheme 30

Note. Before testing any circuits, first verify the 12-volt test light is operating properly. Connect the 12-volt test light to battery ground or to any other known good ground. Touch the lead of the test light to Battery(+). If the test light is operational, it should illuminate brightly.

1. Turn the ignition off.
2. Disconnect the wire harness connectors of the components that contain the ground circuit suspected of containing excessive resistance. NOTE: Check connectors - Clean/repair as necessary.
3. At this time leave all in-line connectors connected.
4. With all the component wire harness connectors disconnected, connect the 12-volt test light to Battery(+).
5. Use the test light lead to lightly probe the ground circuit in the harness connector. Does the test light illuminate brightly? Yes The suspected ground circuit is not open or the condition that originally caused the open or excessive resistance is not present at this time. Another way to check for an open would be to use an ohmmeter and measure the resistance of the ground circuit. While continuing to measure the resistance of the circuit, wiggle the wire harness and connectors to check for an intermittent open or poor connection. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the open could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply. No Repair the open in the ground circuit. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors where the open could occur. One method to help isolate the open is to disconnect any in-line connectors and measure the resistance from one side of the in-line connector to the matching component harness connector. If the open goes away, the open is on the other side of the in-line connector.

TESTING FOR A SHORT BETWEEN MULTIPLE CIRCUITS

Scheme 31

Note. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the multimeter. Take this value and subtract it from the value recorded when measuring the resistance of the circuit being checked (The meter leads can add 0.5 ohm or more of total resistance).

1. Turn the ignition off.
2. Disconnect the wire harness connectors of the components that contain the circuits that are suspected of being shorted together. NOTE: Check connectors - Clean/repair as necessary.
3. At this time leave all in-line connectors connected.
4. With all the component wire harness connectors disconnected, use a multimeter set to Ohms (ohms), and measure the resistance between the applicable circuits in one of the harness connectors.
5. Use one lead of the multimeter and carefully probe the circuit suspected of being shorted.
6. Use the other lead of the meter and one at a time, carefully probe the other circuits in the harness connector. Is the resistance below 10k ohms when probing any two circuits? Yes Repair the short between the circuits. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur. One method to help isolate the short is to disconnect any in-line connectors that the circuit being tested runs through and measure for the short again. If the short goes away, the short is on the other side of the in-line connector. No The circuit is not shorted or the condition that originally caused the short may not be present at this time. Continue to measure the resistance and wiggle the wire harness and connectors while checking for an intermittent short. NOTE: By disconnecting the wire harness connectors you may have eliminated the source that was causing the short. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the short could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply.

TESTING FOR AN OPEN CIRCUIT USING AN OHMMETER

Scheme 32

Note. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the multimeter. Take this value and subtract it from the value recorded when measuring the resistance of the circuit being checked (The meter leads can add 0.5 ohm or more of total resistance).

1. Turn the ignition off.
2. Disconnect the wire harness connectors of the components that contain the circuit suspected of being open. NOTE: Check connectors - Clean/repair as necessary.
3. At this time leave all in-line connectors connected.
4. With the component wire harness connectors disconnected, use a multimeter set to Ohms (ohms), and measure the resistance of the circuit.
5. Use one lead of the meter and probe the circuit in one harness connector.
6. Use the other lead of the meter and probe the same circuit in the other harness connector. Is the resistance in the circuit below 10k ohms? Yes The circuit does not contain any excessive resistance or the condition that originally caused the excessive resistance may not be present at this time. Continue to measure the resistance of the circuit, wiggle the wire harness and connectors to check for an intermittent open or poor connection. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the open could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply. No Repair the excessive resistance in the circuit between the two wire harness connectors. Using the wiring diagram as a guide, trace the circuit and check for any in-line connectors where the open or excessive resistance could occur. One method to help isolate the open is to disconnect any in-line connectors and measure the resistance from one side of the in-line connector to the matching component harness connector. If the open or excessive resistance is not present, the open or excessive resistance is on the other side of the in-line connector.

TESTING FOR PARASITIC DRAW

Note. For a more accurate current draw reading, wait 20 minutes to make sure all modules have powered down before continuing. Some modules may stay powered up longer than others.

Scheme 33

Turn the ignition off.

1. Disconnect the Negative battery cable (ground).
2. Using a multimeter, set the multimeter leads up to properly measure Amperage.
3. Connect the ground lead that is plugged into the COM port of the multimeter to the Negative battery post/terminal.
4. Connect the other lead of the multimeter that is plugged into the Amp port of the multimeter to the Negative battery cable. CAUTION: Do not crank the engine or turn on any accessories that may draw more than 10 Amps. You may open the protective fuse in the multimeter.
5. While monitoring the amperage reading on the multimeter, begin to remove fuses (one at a time) from each fuse location on the vehicle and see if the amperage drops. NOTE: Only remove one fuse at a time until the cause of the voltage draw is determined. Many vehicles have multiple fuse locations on the vehicle.
6. If the amperage does not drop, install the fuse you just removed and remove the next fuse. Does the amperage drop to between 0.02 to 0.04 of an Amp when removing any fuses? Yes Use the wiring diagram as a guide to help indicate what components or modules are powered by the fuse. At this point you can install the fuse and begin disconnecting the components powered by the fuse. When the amperage drops after disconnecting a component this will indicate which component is at fault. It is important to know how long some modules are designed to remain awake. You don't want to replace a component that is operating normally. The condition that originally caused the draw may not be present at this time. No The condition that originally caused the draw may not be present at this time. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded ground terminals. Perform any Technical Service Bulletins (TSBs) that may apply.

LOAD TESTING A GROUND CIRCUIT

DIAGNOSTIC LOAD TEST (GROUND CIRCUIT)

Scheme 34

1. Disconnect the connector from the device(s) to gain access and isolate the terminal for the circuit being tested.
2. Connect the positive lead of the load test tool to the positive side of the battery.
3. Using an approved connector back probe tool, connect the negative lead of the load test tool to the circuit being tested at point (A). CAUTION: Use only approved connector back probe tools when back probing a connector so as not to cause damage to the terminals or insulation of the connector. Damage to the terminals can cause poor terminal contact or retention. Damage to the insulation can introduce corrosion due to water infiltration. Does the bulb light bright, when compared to a direct battery connection? Yes The circuit being tested can carry a load, check other circuits, connectors and terminals for concerns. No Repair the circuit, connector or terminal that has an open or excessive resistance. Perform any related Recalls or Technical Service Bulletins (TSBs) that may apply.

LOAD TESTING A BATTERY OR IGNITION FEED CIRCUIT

DIAGNOSTIC LOAD TEST (BATTERY/IGNITION FEED CIRCUIT)

Scheme 35

1. Disconnect the connector from the device(s) to gain access and isolate the terminal for the circuit being tested.
2. Using an approved connector back probe tool, connect the positive lead of the load test tool to the circuit being tested at point (A).
3. Connect the negative lead of the load test tool to the negative side of the battery or ground. CAUTION: Use only approved connector back probe tools when back probing a connector so as not to cause damage to the terminals or insulation of the connector. Damage to the terminals can cause poor terminal contact or retention. Damage to the insulation can introduce corrosion due to water infiltration. Does the bulb light bright, when compared to a direct battery connection? Yes The circuit being tested can carry a load, check other circuits, connectors and terminals for concerns. No Repair the circuit, connector or terminal that has an open or excessive resistance. Perform any related Recalls or Technical Service Bulletins (TSBs) that may apply.

LOAD TESTING A BATTERY OR IGNITION FEED CIRCUIT AND GROUND CIRCUIT

DIAGNOSTIC LOAD TEST (BATTERY FEED & GROUND CIRCUIT)

Scheme 36

1. Disconnect the connector from the device(s) to gain access and isolate the terminal for the circuit being tested.
2. Using an approved connector back probe tool, connect the positive lead of the load test tool to the circuit being tested at point (A).
3. Using an approved connector back probe tool, connect the negative lead of the load test tool to the circuit being tested at point (B). CAUTION: Use only approved connector back probe tools when back probing a connector so as not to cause damage to the terminals or insulation of the connector. Damage to the terminals can cause poor terminal contact or retention. Damage to the insulation can introduce corrosion due to water infiltration. Does the bulb light bright, when compared to a direct battery connection? Yes The circuit being tested can carry a load, check other circuits, connectors and terminals for concerns. No Test the circuits individually to determine which circuit is the cause of the test failure. Repair the circuit, connector or terminal that has an open or excessive resistance. Perform any related Recalls or Technical Service Bulletins (TSBs) that may apply.

LOAD TESTING A CIRCUIT FOR AN OPEN OR HIGH RESISTANCE

DIAGNOSTIC LOAD TEST (OPEN/HIGH RESISTANCE CIRCUIT)

Scheme 37

1. Disconnect all components from the circuit being tested.
2. Connect the positive lead of the load test tool to the positive side of the battery (A).
3. Using an approved connector back probe tool, connect the negative lead of the load test tool to the circuit being tested at point (B).
4. Using an approved connector back probe tool, connect a jumper wire to the circuit being tested at point (C).
5. Then connect the other end of the jumper wire to the negative side of the battery or ground (D). CAUTION: Use only approved connector back probe tools when back probing a connector so as not to cause damage to the terminals or insulation of the connector. Damage to the terminals can cause poor terminal contact or retention. Damage to the insulation can introduce corrosion due to water infiltration. Does the bulb light bright, when compared to a direct battery connection? Yes The circuit being tested can carry a load, check other circuits, connectors and terminals for concerns. No Repair the circuit, connector or terminal that has an open or excessive resistance. Perform any related Recalls or Technical Service Bulletins (TSBs) that may apply.

TESTING FOR VOLTAGE DROP

Scheme 38

1. Turn the ignition off.
2. Use the wiring diagram as a guide, trace the circuit being tested and locate the components related to the circuit.
3. Set the multimeter to measure DC voltage.
4. Carefully back probe the two component harness connectors of the circuit being tested. WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury. NOTE: If you are testing the starting circuit, disable the engine so the engine does not start.
5. Crank the engine for five seconds if you are testing the starting circuit and monitor the multimeter voltage reading.
6. For circuits that don't require the engine running, turn the ignition on.
7. For circuits that require the engine running, start the engine. NOTE: If the circuit you are checking needs to be operating, such as the Blower Motor or a Lamp, do so now.
8. Monitor the voltage reading.
9. The voltmeter will show the difference in voltage between the two points. Is the voltage less than 0.2 of a Volt? Yes At this time the circuit is functioning properly. Continue to measure the voltage between the components and wiggle the wire harness and connectors while checking for an intermittent condition. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors where the excessive resistance could occur intermittently. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply. No Repair the excessive resistance in the circuit. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors where the excessive resistance may occur. Look for any chafed, pierced, pinched, or partially broken wires. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related wire harness connectors. Perform any Technical Service Bulletins (TSBs) that may apply.

Scheme 39

All ESD sensitive components are solid state and a symbol is used to indicate this. When handling any component with this symbol, comply with the following procedures to reduce the possibility of electrostatic charge build up on the body and inadvertent discharge into the component. If it is not known whether the component is ESD sensitive, assume that it is.

Perform the following procedure when handling ESD sensitive components

1. Always touch a known good ground before handling the component. This should be repeated while handling the component and more frequently after sliding across a seat, sitting down from a standing position, or walking a distance.
2. Avoid touching electrical terminals of the component, unless instructed to do so by a written procedure.
3. When using a voltmeter, be sure to connect the ground lead first.
4. Do not remove the component from its protective packing until it is time to install the component.
5. Before removing the component from its package, ground the package to a known good ground on the vehicle.