Engine Controls - Tests W/codes: Other Dodge Ram Wagon B1500

Malfunction Indicator Light (MIL)

MIL may also be referred to as CHECK ENGINE light. MIL is located in instrument panel. When ignition is first turned on, MIL should come on and remain on for 2-3 seconds to verify bulb and circuit operation, and then go off.

PCM monitors several different engine control system circuits. PCM is located in engine compartment. See PCM LOCATION table. If a malfunction occurs which affects vehicle emissions, a Diagnostic Trouble Code (DTC) is stored in PCM and PCM enters limp-in mode. In limp-in mode, PCM substitutes values for failed component to continue engine operation, but loss of good driveability may result. When DTC is stored in PCM, PCM will turn on MIL and MIL will remain on steady.

If PCM detects active engine misfire severe enough to cause catalytic converter damage, MIL will immediately turn on to warn driver of possible damage and DTC will be stored. On manual transmission vehicles, MIL will either flash or light continuously during an active engine misfire. On all vehicles, PCM will turn off MIL when malfunction is not detected during 3 consecutive engine misfire or fuel system monitor tests. PCM performs engine misfire and fuel system monitor tests within predetermined engine speed (RPM) and load operating conditions. MIL may be turned off by PCM, however, a DTC may remain stored depending on type of malfunction detected.

PCM LOCATION

Note. For additional information about engine misfire and fuel system monitoring, see ON-BOARD DIAGNOSTICS.

On-Board Diagnostics

Powertrain Control Module (PCM) monitors several different engine control system circuits. If malfunction occurs, PCM will store a Diagnostic Trouble Code (DTC) when malfunction is detected, and PCM will enter limp-in mode. In limp-in mode, PCM substitutes values for failed component to continue engine operation, but loss of good driveability may result.

PCM contains electronic circuit monitors that monitor fuel, vehicle emissions, engine and ignition system performance. Monitors use information from various sensor circuits for system monitoring. Monitors do not indicate a specific component failure, but indicate an implied failure within a specified system, and that problem must be diagnosed. If any monitor detects a problem affecting vehicle emissions, a DTC will be stored in PCM. The following monitors are used

1. Engine Misfire Monitor
2. Fuel System Monitor
3. Oxygen Sensor Monitor
4. Oxygen Sensor Heater Monitor
5. Catalyst Monitor
6. EVAP System Leak Detection Monitor

MIL may be turned off by PCM, however, a DTC may remain stored depending on type of malfunction detected. To erase DTCs, see CLEARING DTCS under SELF-DIAGNOSTIC SYSTEM. Once MIL is turned off, PCM must not detect recent malfunction during 40 run/stop engine cycles with engine coolant temperature at least 160°F (71.1°C) on normal operation, or 80 run/stop engine cycles with engine coolant temperature at least 160°F (71.1°C) on engine misfire or fuel system monitor.

PCM also records and stores engine operating conditions when malfunction occurred. This information is referred to as freeze frame data. If malfunction is an engine misfire or fuel system rich or fuel system lean, freeze frame data will be updated with most current information regarding these failures. Freeze frame data recorded is

1. Fuel System Status (Closed Or Open Loop)
2. Load Value (Displayed As Percent)
3. Engine Coolant Temperature
4. Short Term Adaptive (Displayed As Percent)
5. Long Term Adaptive (Displayed As Percent)
6. MAP Vacuum
7. Engine RPM
8. Vehicle Speed Sensor
9. DTC Causing Freeze Frame During Data Recording
10. Freeze Frame Priority

DTCs may be retrieved for system diagnosis by using scan tool only. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM. By using scan tool, self-diagnostic capabilities of this system can simplify testing and reduce diagnostic time. Erasing DTCs also erases freeze frame data. See CLEARING DTCS under SELF-DIAGNOSTIC SYSTEM. System malfunctions are identified as either hard failures or intermittent failures.

Hard Failures

Hard failures cause MIL to illuminate and remain on until problem is repaired. If MIL comes on and remains on during vehicle operation, cause of malfunction must be determined by retrieving DTCs. See RETRIEVING DTCS under SELF-DIAGNOSTIC SYSTEM. If a sensor fails, PCM will use substitute value in its calculations to continue engine operation. In this condition, commonly known as limp-in mode, vehicle runs but driveability will not be optimum.

Intermittent Failures

Intermittent failures may cause MIL to flicker or illuminate and go out after intermittent failure goes away. However, corresponding DTC will be retained in PCM memory. If related failure does not return within a certain time frame, related DTC will be erased from PCM memory. Intermittent failures may be caused by a sensor, connector or wiring related problems. See INACTIVE DTC CONDITION .

SERVICE PRECAUTIONS

Before proceeding with system diagnosis, following precautions must be followed

1. Ensure fuel pressure is released before removing fuel line or fittings, as fuel system is under pressure and may cause personal injury. See «FUEL PRESSURE RELEASE»(ref-139160-S35769876822002042600000) .
2. When using self-diagnostic for diagnosis, DO NOT skip any steps, or incorrect diagnosis may result. Always perform indicated Verification (VER) test after repairs are made.
3. When using a jumper wire, ensure either jumper wire or circuit is fuse-protected.
4. Ensure ignition is off before disconnecting connector from any control module.
5. When checking voltage or continuity at any control module, probe connector for control module from pin side. DO NOT probe wire through insulation or backprobe connector (unless instructed to do otherwise in test procedure).
6. DO NOT cause short circuits when performing electrical tests. This will set additional Diagnostic Trouble Codes (DTCs), making diagnosis of original problem more difficult.
7. Use specified test equipment when performing electrical tests.
8. When checking for spark, ensure no fuel leaks exist and spark plug cable or coil wire is NOT more than 1/4" from engine ground. If spark plug or coil wire is more than 1/4" from engine ground, damage to vehicle electronics and/or Powertrain Control Module (PCM) may result.
9. DO NOT prolong testing of fuel injectors or engine may hydrostatically lock.
10. If replacing PCM, correct vehicle mileage and Vehicle Identification Number (VIN) must be programmed into PCM to prevent DTCs from being set in Anti-lock Brake System (ABS) module and Supplemental Restraint System (SRS) module. See POWERTRAIN CONTROL MODULE PROGRAMMING.
11. If replacing PCM on models with a Sentry Key Immobilizer Module (Skim), secret key data must be updated to enable engine starting. To update secret key data, see POWERTRAIN CONTROL MODULE PROGRAMMING.

POWERTRAIN CONTROL MODULE PROGRAMMING

Connect scan tool to Data Link Connector (DLC). DLC is located below instrument panel near steering column. (Scheme 25) On models with Smart Key Immobilizer Module (SKIM), go to ENGINE and then MISC menus on scan tool. Place SKIM in SECURED ACCESS MODE by using appropriate Personal Identification Number (PIN) for this vehicle. PIN may be obtained from owner, vehicle's invoice, or from the manufacturer. Select UPDATE THE SECRET KEY DATA. Data will be transferred from SKIM to PCM. On all models, use scan tool to enter correct VIN and mileage into PCM. Using scan tool manufacturer's instructions, erase DTCs from ABS and SRS modules.

Scheme 25

RETRIEVING DTCS

Note. Self-diagnostic tests are written specifically for Chrysler's Diagnostic Readout Box-III (DRB-III) scan tool. If using a generic scan tool, ensure scan tool is OBD-II certified. A generic scan tool may not be capable of performing all necessary test functions.

Note. If MIL does not come on for 3 seconds and then go off, bulb may be defective, or problem may exist on circuit (CCD Bus) between PCM and instrument cluster. If problem exists with CCD Bus, this problem may be displayed when using scan tool to retrieve DTCs.

Note. Ensure battery is fully charged before proceeding with test.

1. Attempt to start engine. Turn ignition off. Diagnostic Trouble Codes (DTCs) can only be retrieved using scan tool. Connect scan tool to Data Link Connector (DLC). DLC is located below instrument panel near steering column. (Scheme 25)
2. Turn ignition on, with engine off. Using scan tool manufacturer's instructions, read and record DTC (generic scan tool) or DTC message (DRB-III scan tool), and freeze frame data.
3. If scan tool displays NO RESPONSE, perform «TEST NS-SEL: NO START SELECTION MENU»(ref-139160-S15758901062002042600000). If scan tool will not power up, check for loose cable connections or bad cable. If cable connections and cable are okay, check voltage on DLC power terminal. See appropriate wiring diagram in WIRING DIAGRAMS article. Voltage should be at least 11 volts. If voltage is not as specified, check wiring circuit and necessary fuses.
4. If scan tool displays USER-REQUESTED COLD BOOT ERROR or USER-REQUESTED WARM BOOT ERROR, or any other error message, record entire displayed error message and follow scan tool manufacturer's instructions for information on correcting error.
5. If scan tool displays BUS FAILURE, indicating either a scan tool or BUS circuit failure, to diagnose and correct these conditions, see «VEHICLE COMMUNICATIONS»(ref-689) article in ACCESSORIES & EQUIPMENT.
6. If DTCs are displayed, perform appropriate test(s) listed under SELF-DIAGNOSTIC TESTS. See DTC MESSAGES & CODES table. Once all repairs are made, ensure DTCs are erased from PCM memory. See CLEARING DTCS. If no DTCs are displayed, refer to one of the following: For driveability problems, perform «TEST NTC-1A: NO TROUBLE CODE TEST MENU»(ref-139160-S03555036352002042600000). For no-start problems, perform «TEST NS-SEL: NO START SELECTION MENU»(ref-139160-S15758901062002042600000). For speed control problems and servicing information, see appropriate CRUISE CONTROL SYSTEMS article in ACCESSORIES & EQUIPMENT. For charging system problems, see «GENERATORS & REGULATORS -- TRUCKS & RWD VANS»(ref-1959) article in STARTING & CHARGING SYSTEMS.

Note. Not all DTCs listed in DTC MESSAGES & CODES table are used on all models.

DTC MESSAGES & CODES (1)

CLEARING DTCS

Ensure ignition is off, then turn ignition on, with engine off. Using scan tool manufacturer's instructions, erase DTCs from PCM memory.

FUEL PRESSURE RELEASE

NTC-2A: CHECKING SECONDARY IGNITION

Note. Refer to manufacturer's operation manual for instructions in use of engine analyzer.

1. Connect engine analyzer to engine. Start engine and allow engine to idle. If engine will not idle, maintain engine speed at more than idle. Set scope on engine analyzer to read display or parade pattern. Using spray bottle with water, spray spark plug wires while monitoring secondary ignition pattern. If secondary ignition pattern does not change with water being applied, go to next step. If secondary ignition pattern changes with water being applied, replace spark plug wire as necessary. Perform TEST VER-2A. NOTE: Refer to manufacturer's operation manual for pattern analysis procedure.
2. With engine idling, analyze secondary ignition pattern. If engine will not idle, maintain engine speed at more than idle. If secondary ignition pattern is okay, go to next step. If secondary ignition pattern is not correct, repair indicated component in secondary ignition system. Perform TEST VER-2A.
3. With engine idling, momentarily remove and reinstall spark plug wires from spark plugs while observing the secondary ignition kilovolt line. If engine will not idle, maintain engine speed at more than idle. If open circuit secondary ignition voltage is at least 25 kilovolt, secondary ignition system is okay and test is complete. If open circuit secondary ignition voltage is not at least 25 kilovolt, replace ignition coil. Perform TEST VER-2A.

NTC-3A: CHECKING PCM POWER & GROUND CIRCUITS

1. Turn ignition off. Disconnect PCM connectors. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. Clean and/or repair connectors as necessary. Using a 12-volt test light connected to ground, probe PCM connector, B+ circuit. For wire color, see WIRING DIAGRAMS article. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, repair open B+ circuit. Perform TEST VER-2A.
2. Ensure ignition is off. Ensure PCM connectors are still disconnected. Turn ignition on, with engine off. Using 12-volt test light connected to ground, probe PCM connector, fused ignition switch output circuit. For wire color, see WIRING DIAGRAMS article. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, repair open fused ignition switch output circuit. Perform TEST VER-2A.
3. Turn ignition off. Ensure PCM connectors are still disconnected. Using 12-volt test light connected to ground, probe both PCM connector, ground circuits. For wire color, see WIRING DIAGRAMS article. If test light illuminates brightly on both circuits, go to next step. If test light does not illuminate brightly on both circuits, repair open ground circuit(s). Perform TEST VER-2A.

NTC-3B: CHECKING ECM POWER & GROUND CIRCUITS

1. Turn ignition off. Disconnect ECM connector. Clean and/or repair connector as necessary. Using a 12-volt test light connected to ground, probe both ECM connector, B+ circuits. For wire color, see WIRING DIAGRAMS article. If test light illuminates brightly on both circuits, go to next step. If test light does not illuminate brightly, repair open B+ circuit(s).
2. Ensure ignition is off. Ensure ECM connector is still disconnected. Turn ignition on, with engine off. Using 12-volt test light connected to ground, probe ECM connector, fused ignition switch output circuit. For wire color, see WIRING DIAGRAMS article. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, repair open fused ignition switch output circuit. 3) Turn ignition off. Ensure ECM connector is still disconnected. Using 12-volt test light connected to ground, probe both ECM connector, ground circuits. For wire color, see WIRING DIAGRAMS article. If test light illuminates brightly on both circuits, go to next step. If test light does not illuminate brightly on both circuits, repair open ground circuit(s).

NTC-4A: CHECKING ENGINE VACUUM

Note. Normal vacuum readings vary according to altitude.

Connect vacuum gauge to engine vacuum source. Start engine and allow engine to idle. Note engine vacuum reading. Engine vacuum should be steady and 13-22 in. Hg with engine at idle. While monitoring engine vacuum reading, quickly open and close the throttle several times and then allow engine to idle. If engine vacuum is within specification, test is complete. If engine vacuum is not within specification, perform NTC-13A: CHECKING ENGINE MECHANICAL SYSTEMS test.

NTC-5A: CHECKING FUEL DELIVERY/PRESSURE

1. Turn ignition off. Inspect fuel lines for leaks, kinks or restrictions. Release fuel pressure and repair or replace fuel lines as necessary. Perform TEST VER-2A. If fuel lines are okay, go to next step.
2. Release fuel pressure. Connect fuel pressure gauge to fuel pressure test port. Using scan tool, actuate fuel system test and note fuel pressure. Fuel pressure should be 44.2-54.2 psi (3.23-3.96 kg/cm 2 ). If fuel pressure is within specification, test is complete. If fuel pressure is not within specification, release fuel pressure and replace fuel pump module. Fuel pump module is located in fuel tank. Perform TEST VER-2A.

NTC-9A: CHECKING MINIMUM IDLE AIR FLOW

1. Remove air cleaner. Disconnect vacuum hose from PCV valve. Install Vacuum Fitting (6714) in disconnected hose. Disconnect 3/16" EVAP hose from throttle side of body. Cap 3/16" nipple. Start engine and allow it to idle. Allow engine to reach normal operating temperature. Using scan tool, actuate minimum idle airflow and wait for system to stabilize. If engine speed is 500-900 RPM, stop actuation test. Minimum idle airflow is normal. Test is complete. If engine speed is not as specified, go to next step. WARNING: Clean throttle body in well ventilated area and wear rubber gloves.
2. Stop actuation test. Turn engine off. Remove throttle body. While holding throttle open, spray entire throttle body bore with carburetor/throttle body cleaner. Using soft scuff pad, clean throttle body bore and throttle plate. Using compressed air, dry throttle body. Install throttle body. Start engine and allow it to idle. Using scan tool, actuate minimum idle airflow. If engine speed is 500-900 RPM, test is complete. If engine speed is not as specified, go to next step. NOTE: A vacuum leak may cause IAC motor not to perform correctly.
3. Start engine and allow it to idle. Check engine, brake booster and vacuum hoses for leaks. Repair vacuum leaks as necessary. Perform TEST VER-2A. If no vacuum leaks exist at this time, throttle body is assumed to be defective. Replace throttle body. Perform TEST VER-2A.

NTC-10A: CHECKING HO2S SWITCHING

Note. 1/1 Heated Oxygen Sensor (HO2S) is located in upstream position. On models with 2 upstream HO2S, 1/1 HO2S is located in left upstream position. 1/2 HO2S is located in downstream position. On models equipped with 4 HO2S, 1/2 HO2S is located in left downstream position. 2/1 HO2S is located in right upstream position on models with 2 upstream HO2S.

Note. 1/2 and 1/3 HO2S switching should be slower than 1/1 or 2/1 HO2S switching.

1. Start engine and allow it to idle. Allow engine to reach normal operating temperature. Using scan tool, read HO2S states. If HO2S states are switching between RICH and LEAN, system is functioning properly. Test is complete. If either HO2S is not switching between RICH and LEAN, go to next step.
2. If either HO2S is locked on LEAN, go to next step. If neither HO2S is locked on LEAN, go to step 8).
3. Ensure engine is still idling. Check engine, brake booster and vacuum hoses for leaks. Repair vacuum leaks as necessary. Perform TEST VER-2A. If no vacuum leaks exist, go to next step.
4. Ensure engine is still idling. Using scan tool, read HO2S voltages. If voltage is less than .1 volt for any HO2S, go to next step. If voltage is more than l1 volt for all HO2S, go to step 7). NOTE: For connector terminal identification, see «CONNECTOR IDENTIFICATION»(ref-139160-S09977502222002042600000) . For circuit identification and wiring diagram, see «RAM VAN & RAM WAGON»(ref-575-S40518762292002042600000) wiring diagram in WIRING DIAGRAMS article.
5. Turn ignition off. Disconnect suspected HO2S connector. Disconnect PCM connectors. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. Clean and/or repair connectors as necessary. Using an ohmmeter, check resistance between ground and suspected HO2S connector, signal circuit. If resistance is less than 5 ohms, repair signal circuit for short to ground. Perform TEST VER-2A. If resistance is 5 ohms or more, go to next step.
6. At this time, suspected HO2S is assumed to be defective. Replace HO2S. Perform TEST VER-2A. NOTE: 1/2 and 1/3 HO2S switching should be slower than 1/1 or 2/1 HO2S switching.
7. Turn ignition on, with engine off. Using scan tool, reset adaptive fuel memory. Start engine and allow it to idle for at least 3 minutes. Ensure engine is at normal operating temperature. Using scan tool, read HO2S states. If 1/2 and 1/3 HO2S are switching states slower than 1/1 or 2/1 HO2S, test is complete. If HO2S switching is not as specified, perform NTC-13A: CHECKING ENGINE MECHANICAL SYSTEMS. WARNING: High fuel pressure may be present in fuel lines. Open fuel system with caution. See «FUEL PRESSURE RELEASE»(ref-139160-S35769876822002042600000) .
8. Turn engine off. Release fuel pressure. Connect fuel pressure gauge to fuel rail. Turn ignition on, with engine off. Using scan tool, actuate fuel system test. Allow fuel pressure gauge to stabilize. Stop fuel system actuation test. Monitor fuel pressure gauge for one minute. If fuel pressure gauge reading drops more than 10 psi (.7 kg/cm 2 ), replace leaking fuel pump, fuel lines or injector(s) as necessary. Perform TEST VER-2A. If fuel pressure does not drop as specified, go to next step.
9. Inspect air cleaner and inlet ducts for restrictions. Repair air cleaner and inlet ducts as necessary. Perform TEST VER-2A. If no restrictions exist, perform «NTC-13A: CHECKING ENGINE MECHANICAL SYSTEMS»(ref-139160-S36516009822002042600000) .

NTC-11A: CHECKING HO2S HEATER

Note. 1/1 Heated Oxygen Sensor (HO2S) is located in upstream position. On models with 2 upstream HO2S, 1/1 HO2S is located in left upstream position. On AN body (2WD) with 5.9L engine and BE/BR bodies with 8.0L medium-duty engine, 1/2 Heated Oxygen Sensor (HO2S) is located in pre-catalyst position. On all other bodies, 1/2 HO2S is located in downstream position. On models equipped with 4 HO2S, 1/2 HO2S is located in left downstream position. 1/3 HO2S is used on BE/BR bodies with 8.0L medium-duty engine only and is located in post-catalyst position. 2/1 HO2S is located in right upstream position on models with 2 upstream HO2S.

1. Turn ignition on, with engine off. Using scan tool, actuate HO2S heater test. Wait 2 minutes for HO2S voltages to stabilize. Using scan tool, read HO2S signal voltage. If voltage is one volt or less on all HO2S, stop actuation test. Test is complete. If voltage is more than one volt on any HO2S, stop actuation test and go to next step. NOTE: For connector terminal identification, see «CONNECTOR IDENTIFICATION»(ref-139160-S09977502222002042600000) . For circuit identification and wiring diagram, see «RAM VAN & RAM WAGON»(ref-575-S40518762292002042600000) wiring diagram in WIRING DIAGRAMS article.
2. Turn ignition off. Disconnect suspected HO2S connector. Clean and/or repair connector as necessary. Using an ohmmeter, check resistance between ground and HO2S connector, heater ground circuit. If resistance is less than one ohm, go to next step. If resistance is one ohm or more, repair open heater ground circuit. Perform TEST VER-2A. NOTE: Voltage remaining above one volt on any HO2S, indicates a problem with that HO2S. NOTE: For connector terminal identification, see «CONNECTOR IDENTIFICATION»(ref-139160-S09977502222002042600000) . For circuit identification and wiring diagram, see «RAM VAN & RAM WAGON»(ref-575-S40518762292002042600000) wiring diagram in WIRING DIAGRAMS article.
3. Turn ignition on, with engine off. Using scan tool, read HO2S signal voltage. If voltage is one volt or less on all HO2S, stop actuation test. Test is complete. If voltage is more than one volt on any HO2S, turn ignition off. Disconnect suspect HO2S connector. Clean and/or repair connector as necessary. Using a voltmeter, check voltage on HO2S connector, ASD relay output circuit. If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, repair open ASD relay output circuit. Perform TEST VER-2A.
4. At this time, suspected HO2S is assumed to be defective. Replace HO2S. Perform TEST VER-2A.

NTC-12A: CHECKING IAC MOTOR

1. Start engine an allow it to reach normal operating temperature. Using scan tool, actuate IAC motor to 1400 RPM. If engine speed is 1300-1500 RPM, stop actuation. IAC motor is operating properly. If engine speed is not 1300-1500 RPM, go to next step.
2. Start engine and allow it to idle. Check engine, brake booster and vacuum hoses for leaks. Repair vacuum leaks as necessary. Perform TEST VER-2A. If no vacuum leaks exist, go to next step.
3. Turn ignition off. Disconnect IAC motor connector. IAC motor is located on throttle body. Visually inspect connector for corroded, damaged, pushed-out or miswired terminals. Repair connector and terminals as necessary. Perform TEST VER-2A. If connector and terminals are okay, go to next step. NOTE: For connector terminal identification, see «CONNECTOR IDENTIFICATION»(ref-139160-S09977502222002042600000) . For circuit identification and wiring diagram, see «RAM VAN & RAM WAGON»(ref-575-S40518762292002042600000) wiring diagram in WIRING DIAGRAMS article.
4. Ensure ignition is off. Ensure IAC motor connector is still disconnected. Disconnect PCM connectors. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. Clean and/or repair connectors as necessary. Using an ohmmeter, check resistance between ground and PCM connector, IAC driver No. 1 circuit. If resistance is less than 5 ohms, repair driver No. 1 circuit for short to ground. Perform TEST VER-2A. If resistance is 5 ohms or more, go to next step.
5. Ensure ignition is off. Ensure IAC motor and PCM connectors are still disconnected. Using ohmmeter, check resistance between ground and PCM connector, IAC driver No. 2 circuit. If resistance is less than 5 ohms, repair driver No. 2 circuit for short to ground. Perform TEST VER-2A. If resistance is 5 ohms or more, go to next step.
6. Ensure ignition is off. Ensure IAC motor and PCM connectors are still disconnected. Using ohmmeter, check resistance between ground and PCM connector, IAC driver No. 3 circuit. If resistance is less than 5 ohms, repair driver No. 3 circuit for short to ground. Perform TEST VER-2A. If resistance is 5 ohms or more, go to next step.
7. Ensure ignition is off. Ensure IAC motor and PCM connectors are still disconnected. Using ohmmeter, check resistance between ground and PCM connector, IAC driver No. 4 circuit. If resistance is less than 5 ohms, repair driver No. 4 circuit for short to ground. Perform TEST VER-2A. If resistance is 5 ohms or more, go to next step. NOTE: Voltage may switch or remain constant in this step.
8. Ensure ignition is off. Ensure IAC motor connector is still disconnected. Reconnect PCM connectors. Turn ignition on, with engine off. Using scan tool in actuator tests mode, actuate IAC stepper motor. Using a voltmeter, check voltage on IAC motor connector, driver No. 1 circuit. If voltage is more than 5 volts at any time, go to next step. If voltage is not 5 volts or more at any time, perform appropriate DTC P0505: IAC MOTOR CIRCUIT test. NOTE: Voltage may switch or remain constant in this step.
9. Ensure ignition is off. Ensure IAC motor connector is still disconnected. Ensure ignition is on, with engine off. Using scan tool in actuator tests mode, actuate IAC stepper motor. Using voltmeter, check voltage on IAC motor connector, driver No. 2 circuit. If voltage is more than 5 volts at any time, go to next step. If voltage is not 5 volts or more at any time, perform appropriate DTC P0505: IAC MOTOR CIRCUIT test. NOTE: Voltage may switch or remain constant in this step.
10. Ensure ignition is off. Ensure IAC motor connector is still disconnected. Ensure ignition is on, with engine off. Using scan tool in actuator tests mode, actuate IAC stepper motor. Using voltmeter, check voltage on IAC motor connector, driver No. 3 circuit. If voltage is more than 5 volts at any time, go to next step. If voltage is not 5 volts or more at any time, perform appropriate DTC P0505: IAC MOTOR CIRCUIT test. NOTE: Voltage may switch or remain constant in this step.
11. Ensure ignition is off. Ensure IAC motor connector is still disconnected. Ensure ignition is on, with engine off. Using scan tool in actuator tests mode, actuate IAC stepper motor. Using voltmeter, check voltage on IAC motor connector, driver No. 4 circuit. If voltage is more than 5 volts at any time, go to next step. If voltage is not 5 volts or more at any time, perform appropriate DTC P0505: IAC MOTOR CIRCUIT test.
12. Turn ignition off. Disconnect PCM connectors. Visually inspect connectors for corroded, damaged, pushed-out or miswired terminals. Repair connectors and terminals as necessary. Perform TEST VER-2A. If connectors and terminals are okay, go to next step.
13. Ensure ignition is off. Ensure IAC motor and PCM connectors are still disconnected. Using an ohmmeter, check resistance between IAC motor connector, driver No. 2 circuit, and driver No. 3 and driver No. 4 circuits. If resistance is 5 ohms or more between all circuits, go to next step. If resistance is less than 5 ohms between any 2 circuits, repair driver circuits that are shorted together. Perform TEST VER-2A.
14. Ensure ignition is off. Ensure IAC motor and PCM connectors are still disconnected. Using ohmmeter, check resistance between IAC motor connector, driver No. 1 circuit and each remaining driver circuit. If resistance is 5 ohms or more between all circuits, go to next step. If resistance is less than 5 ohms between any 2 circuits, repair driver circuits that are shorted together. Perform TEST VER-2A.
15. Ensure ignition is off. Ensure IAC motor and PCM connectors are still disconnected. Using ohmmeter, check resistance between IAC motor connector, driver No. 3 circuit (Brown/White wire) and driver No. 4 circuit (Violet/Black wire). If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair driver No. 3 circuit for short to driver No. 4 circuit. Perform TEST VER-2A.
16. At this time, IAC motor is assumed to be defective. Replace IAC motor. Perform TEST VER-2A.

NTC-13A: CHECKING ENGINE MECHANICAL SYSTEMS

Note. If coming to this test from a Heated Oxygen Sensor (HO2S) test, and rich or lean condition is not corrected after checking items listed below, replace Powertrain Control Module (PCM). Perform TEST VER-2A.

1. At this point in diagnostic test procedure, all engine control systems have been determined to be operating as designed and not causing a driveability problem. Following additional items should be checked as possible causes: Ensure engine vacuum is at least 13 in. Hg In Neutral: Check valve timing: Check engine compression: Check for exhaust system restrictions: Check PCV system for proper function: Ensure engine drive sprocket is properly positioned: Check torque converter stall speed (A/T): Check power brake booster for internal vacuum leak: Check for fuel contamination: Ensure injector control wire is connected to correct fuel injector and injector is not plugged or restricted: Check for pertinent Technical Service Bulletins (TSBs): If equipped with distributor, set distributor position. Go to next step. WARNING: Avoid contact with moving engine parts. NOTE: Setting distributor position does not adjust ignition timing. Ignition timing is controlled by PCM.
2. Connect scan tool to data link connector. Select SET SYNC from scan tool menu. Start engine and allow it to idle. Observe scan tool display. If scan tool does not display IN RANGE, loosen distributor hold-down clamp bolt and rotate distributor until reading is as close to zero degrees as possible, and IN RANGE message is displayed. Tighten hold-down clamp bolt to 16.7 ft. lbs. (22.5 N.m).

NTC-13B: CHECKING ENGINE MECHANICAL SYSTEMS

At this point in diagnostic test procedure, all engine control systems have been determined to be operating as designed and not causing a driveability problem. Following additional items should be checked as possible causes

1. Check fuel injection pump for malfunction, misadjustment or incorrect pump timing
2. Check for air in fuel system
3. Check for restricted or damaged injector nozzle
4. Check for improper fuel
5. Check for clogged fuel filter
6. Check for blocked or restricted fuel injection lines
7. Check for leaking or damaged fuel injection lines or loose connections
8. Check for empty fuel tank or blocked fuel tank vent
9. Check for clogged or restricted air filter
10. Check for blocked or leaking intercooler
11. Check for low or uneven engine compression
12. Check for misadjusted low idle
13. Check for throttle lever not reaching full throttle position.

NTC-14A: CHECKING BTS

Turn ignition on, engine off. Using scan tool, read and record Battery Temperature Sensor (BTS) value. Using a thermometer, read ambient temperature near battery. If BTS value is not within 10 degrees of thermometer reading, replace BTS. BTS is located under battery. Perform TEST VER-2A. If BTS value is within 10 degrees of thermometer reading, BTS is operating properly. Test passed.

NTC-15A: CHECKING BRAKE SWITCH

1. If vehicle is not equipped with Speed Control (S/C), go to step 5). If vehicle is equipped with S/C, go to next step. NOTE: For circuit identification and wiring diagram, see appropriate wiring diagram in WIRING DIAGRAMS article.
2. Turn ignition on, with engine off. Ensure brake pedal is not pressed. Using scan tool, actuate S/C solenoids. Using a 12-volt test light connected to ground, probe brake switch connector, s/C brake switch output circuit. Press brake pedal. If test light goes off when brake pedal is pressed and comes on when pedal is released, go to step 5). If test light does not go off when pedal is pressed and come on when pedal is released, go to next step.
3. Check brake switch adjustment. Adjust brake switch as necessary. Perform TEST VER-2A. If brake switch adjustment is okay, go to next step.
4. At this time, brake switch is assumed to be defective. Replace brake switch. Perform TEST VER-2A.
5. Using scan tool, read brake switch input while pressing and releasing brake pedal. If scan tool reading corresponds to position of brake pedal, brake switch is functioning properly. Test passed. If scan tool reading does not correspond to position of brake pedal (PRESSED or RELEASED) on TJ and XJ body, replace brake switch. Perform TEST VER-2A. On all other bodies, go to next step. NOTE: For circuit identification and wiring diagram, see appropriate wiring diagram in WIRING DIAGRAMS article.
6. Disconnect brake switch connector. Clean and/or repair connector as necessary. Perform TEST VER-2A. Using an ohmmeter, check resistance between ground and brakelight switch connector, ground circuit. If resistance is 5 ohms or more, repair open ground circuit. Perform TEST VER-2A. If resistance is less than 5 ohms, go to next step.
7. Turn ignition off. Reconnect brake switch connector. Turn ignition on, with engine off. Ensure brake pedal is not pressed. Using a 12-volt test light connected to ground, backprobe brake switch connector, B+ circuit. If test light illuminates brightly, go to next step. If test light does not illuminate brightly, repair open B+ circuit. Perform TEST VER-2A.
8. Turn ignition off. Disconnect brake switch connector. Disconnect PCM connectors. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. Clean and/or repair connectors as necessary. Using an ohmmeter, check resistance of brake switch sense circuit between brake switch connector and PCM. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open brake switch sense circuit. Perform TEST VER-2A.
9. Ensure ignition is off. Ensure brake switch connector is still disconnected. Reconnect PCM connector. Connect a jumper wire between ground and brakelight switch connector, brake switch sense circuit. Using scan tool, read brake switch status. If scan tool displays RELEASED, replace brake switch. Perform TEST VER-2A. If scan tool does not display RELEASED, go to next step.
10. Check brake switch adjustment. Adjust brake switch as necessary. Perform TEST VER-2A. If brake switch adjustment is okay, go to next step.
11. At this time, PCM is assumed to be defective. Replace PCM. Perform TEST VER-2A.

NTC-16A: CHECKING EVAP SYSTEM

1. Carefully inspect vacuum hoses for proper routing and pinched or plugged hoses from engine to EVAP purge solenoid and to fuel tank. EVAP purge solenoid is located on a bracket mounted in engine compartment. See EVAP PURGE LOCATION table. A vacuum hose routing schematic can be found on Vehicle Emission Control Information (VECI) label. VECI label is located in engine compartment, in front of radiator. Repair hoses as necessary. Perform TEST VER-6. If hoses are okay, go to next step. FUEL PRESSURE SPECIFICATIONS Application Location AB Body Left Front Inner Fender
2. Start engine and allow it to idle until engine coolant temperature is at least 170°F (76.7°C). Turn engine off. Disconnect EVAP purge solenoid-to-EVAP canister vacuum hose at EVAP purge solenoid. Start engine and allow it to idle. There should be no vacuum flow through EVAP purge solenoid for 1-2 minutes. If vacuum flow exists through EVAP purge solenoid within one minute, go to next step. If no vacuum flow exists through EVAP purge solenoid within one minute, go to step 6).
3. Turn engine off. Inspect vacuum hose and line from EVAP purge solenoid to EVAP canister for being disconnected, ripped or cut. If vacuum hose or line is disconnected, ripped or cut open, go to next step. If vacuum hose or line is not disconnected, ripped or cut open, ensure vacuum hose and line are clean and replace EVAP canister. Perform TEST VER-6.
4. Ensure ignition is off. Inspect vacuum hose and line from EVAP purge solenoid to EVAP canister for being disconnected, ripped or cut. If vacuum hose or line is disconnected, ripped or cut open, repair vacuum line or hose as necessary and replace EVAP purge solenoid. Perform TEST VER-6. If vacuum hose or line is not ripped or cut open, go to next step.
5. Ensure ignition is off. Remove EVAP purge solenoid. Tap EVAP purge solenoid ports against a clean, solid surface. If foreign material falls out of ports, replace EVAP purge solenoid. Perform TEST VER-6. If no foreign material falls out of ports, go to next step. CAUTION: DO NOT apply more than 5 psi (.35 kg/cm 2 ) air pressure on vacuum hose.
6. Turn engine off. Ensure EVAP purge solenoid-to-EVAP canister vacuum hose is still disconnected at EVAP purge solenoid. Attempt to blow air through EVAP solenoid-to-EVAP canister hose. If air flows, go to next step. If air does not flow, go to step 8).
7. Start engine and allow it to idle until engine coolant temperature is at least 170°F (76.7°C). Turn engine off. Disconnect EVAP purge solenoid-to-EVAP canister vacuum hose at EVAP purge solenoid. Start engine and allow it to idle. After 90 seconds, ensure vacuum flow cycles intermittently through EVAP purge solenoid. If vacuum flow cycles intermittently through EVAP purge solenoid after 90 seconds, test is complete. If vacuum flow does not cycle intermittently through EVAP purge solenoid after 90 seconds, replace EVAP purge solenoid. Perform TEST VER-6. CAUTION: DO NOT apply more than 5 psi (.35 kg/cm 2 ) air pressure on vacuum hose.
8. Ensure ignition is off. Disconnect EVAP purge solenoid-to-EVAP canister vacuum hose at EVAP canister. Attempt to blow air through EVAP solenoid-to-EVAP canister hose. If air flows, go to next step. If air does not flow, go to step replace EVAP canister. Perform TEST VER-6. If air does not flow, repair or replace vacuum line. Perform TEST VER-6.

NTC-17A: CHECKING IAT SENSOR

Note. When performing this test, DO NOT allow more than 5 minutes between measuring temperature of Intake Air Temperature (IAT) sensor with scan tool and measuring the air temperature inside of intake manifold with temperature probe.

Turn ignition on, engine off. Using scan tool, read and record IAT sensor value. Remove IAT sensor. Using a thermometer, read temperature inside IAT sensor opening. If IAT sensor value is within 10 degrees of thermometer reading, reinstall IAT sensor. IAT sensor is operating properly. Test is complete. If IAT sensor value is not within 10 degrees of thermometer reading, replace IAT sensor. Perform TEST VER-2A.

NTC-18A: CHECKING P/N SWITCH (A/T)

1. Apply parking brake. Turn ignition on, with engine off. Using scan tool, read Park/Neutral (P/N) position switch input state. Move gear selector in and out of Park and Drive while observing scan tool display. If display corresponds with gear selector position, system is functioning properly. Test is complete. If display does not correspond with gear selector position, go to next step. NOTE: For connector terminal identification, see «CONNECTOR IDENTIFICATION»(ref-139160-S09977502222002042600000) . For circuit identification and wiring diagram, see «RAM VAN & RAM WAGON»(ref-575-S40518762292002042600000) wiring diagram in WIRING DIAGRAMS article.
2. Turn ignition off. Place gear selector in Park. Disconnect Powertrain Control Module (PCM) connectors. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. Clean and/or repair connectors as necessary. Using an ohmmeter, check resistance between ground and P/N switch sense circuit. Move gear selector in and out of Park and Drive while observing scan tool display. If resistance stays less than 5 ohms at all times, go to next step. If resistance does not stay less than 5 ohms at all times, repair P/N switch sense circuit for short to ground. Perform TEST VER-2A.
3. Ensure ignition is off. Ensure PCM connectors are still disconnected. Disconnect P/N switch connector. P/N switch is located on side of transmission. Clean and/or repair connector as necessary. Using ohmmeter, check resistance of P/N switch sense circuit between P/N switch connector and PCM. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open P/N switch sense circuit. Perform TEST VER-2A.
4. Ensure ignition is off. Ensure PCM connectors are still disconnected. Reconnect P/N switch connector. Using an ohmmeter, check resistance between ground and P/N switch sense circuit. Move gear selector in and out of Park and Drive while observing scan tool display. If resistance switches from less than 5 ohms to more than 5 ohms, replace PCM. Perform TEST VER-2A. If resistance does not switch from less than 5 ohms to more than 5 ohms, go to next step.
5. At this time, P/N switch is assumed to be defective. Replace P/N switch. Perform TEST VER-2A.

NTC-19A: CHECKING OIL PRESSURE SENSOR

1. Turn ignition off. Check and correct oil level as necessary. While holding down TRIP ODOMETER button and observing oil pressure gauge, turn ignition on, with engine off. Instrument cluster self-test will now run for all gauges and lamps. If oil pressure gauge does not reach calibration points 0, 1/2 and FULL, replace oil pressure gauge. Perform TEST VER-2A. If oil pressure gauge reaches calibration points, go to next step.
2. Turn ignition off. Turn ignition on, with engine off. If oil pressure gauge reads FULL at all times with ignition on, go to next step. If oil pressure gauge does not read FULL at all times with ignition on, go to step 4). NOTE: For connector terminal identification, see «CONNECTOR IDENTIFICATION»(ref-139160-S09977502222002042600000) . For circuit identification and wiring diagram, see «RAM VAN & RAM WAGON»(ref-575-S40518762292002042600000) wiring diagram in WIRING DIAGRAMS article.
3. Turn ignition off. Disconnect oil pressure sensor connector. Clean and/or repair connector as necessary. Turn ignition on, with engine off. If oil pressure gauge does not read FULL at all times with ignition on, replace oil pressure sensor. Perform TEST VER-2A. If oil pressure gauge reads FULL at all times with ignition on, repair short to ground in oil pressure sensor connector, signal circuit. Perform TEST VER-2A.
4. Turn ignition off. Disconnect oil pressure sensor connector. Clean and/or repair connector as necessary. Connect a jumper wire across oil pressure sensor connector. Turn ignition on, with engine off. If oil pressure gauge does not read FULL at all times with ignition on, go to step 7).
5. Turn ignition off. Remove oil pressure sensor. Install oil pressure gauge in oil pressure sensor opening. Start engine and allow it to idle. Record oil pressure. If oil pressure is 4 psi (.28 kg/cm 2 ) or more at idle, go to next step. If oil pressure is 4 psi (.28 kg/cm 2 ) or less with engine at idle, repair mechanical engine oil pressure problem as necessary. Perform TEST VER-2A.
6. Turn engine off. Ensure oil pressure sensor is still removed. Install oil pressure gauge in oil pressure sensor opening. Start engine and allow it to reach normal operating temperature. Read oil pressure. If oil pressure is not at least 4 psi (.28 kg/cm 2 ), repair mechanical engine oil pressure problem as necessary. Perform TEST VER-2A. If oil pressure is at least 4 psi (.28 kg/cm 2 ), replace oil pressure sensor. Perform TEST VER-2A. NOTE: For circuit identification and wiring diagram, see appropriate wiring diagram in WIRING DIAGRAMS article.
7. Using a 12-volt test light connected to battery voltage, probe oil pressure sensor connector, sensor ground circuit. If test light does not illuminate, go to next step. If test light illuminates, repair open oil pressure sensor signal circuit. Perform TEST VER-2A.
8. At this time, sensor ground circuit is assumed to be open. Repair open sensor ground circuit. Perform TEST VER-2A.

NTC-20A: CHECKING A/C SYSTEM

1. If DTC P0645: A/C CLUTCH RELAY CIRCUIT is present, perform appropriate DTC P0645: A/C CLUTCH RELAY CIRCUIT test. If DTC P0645: A/C CLUTCH RELAY CIRCUIT is not present, go to next step.
2. Turn ignition on, with engine off. Using scan tool, monitor A/C REQUEST state. Turn A/C switch on and A/C fan on high. If A/C REQUEST state does not change, go to step 10). If A/C REQUEST state changes, go to next step.
3. Ensure ignition is on, with engine off. Using scan tool, monitor A/C SELECT state. Turn A/C switch on and off several times. If A/C SELECT state does not change, repair open A/C select circuit. Perform TEST VER-2A. If A/C SELECT state changes, go to next step.
4. Ensure ignition is on, with engine off. Using scan tool, actuate A/C clutch relay. If A/C clutch actuates, A/C clutch is operating properly at this time. Test is complete. If A/C clutch does not actuate, go to next step.
5. Turn ignition off. Disconnect A/C clutch connector. Clean and/or repair connector as necessary. Turn ignition on, with engine off. Using scan tool, actuate A/C clutch relay. Connect a 12-volt test light across A/C clutch connector terminals. If test light blinks, replace A/C clutch coil. Perform TEST VER-2A. If test light does not blink, go to next step. NOTE: For circuit identification and wiring diagram, see appropriate wiring diagram in WIRING DIAGRAMS article.
6. Turn ignition off. Remove A/C clutch relay. A/C clutch relay is located in Power Distribution Center (PDC). PDC is located next to battery. Refer to label under PDC cover for relay location. Disconnect A/C clutch connector. Clean and/or repair connectors as necessary. Using an ohmmeter, check resistance of A/C clutch relay output circuit from A/C clutch relay connector to A/C clutch coil. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open A/C clutch relay output circuit. Perform TEST VER-2A.
7. Ensure ignition is off. Ensure A/C clutch relay is still removed. Reconnect A/C clutch connector. Using a 12-volt test light connected to ground, probe A/C clutch relay connector, fused B+ circuit. If test light does not illuminate brightly, repair open fused B+ circuit. Perform TEST VER-2A. If test light illuminates brightly, go to next step.
8. Ensure ignition is off. Disconnect A/C clutch connector. Clean and/or repair connector as necessary. Using an ohmmeter, check resistance between ground and A/C clutch connector, ground circuit. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open ground circuit. Perform TEST VER-2A.
9. At this time, A/C clutch relay is assumed to be defective. Replace A/C clutch relay. Perform TEST VER-2A.
10. Turn ignition off. Ensure A/C system is properly charged. Recharge system as necessary. Perform TEST VER-2A. If A/C system is properly charged, go to next step
11. Check high pressure cut-off switch. See «HIGH PRESSURE CUT-OUT SWITCH»(ref-205-S11201870042000030800000) in MANUAL A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING. Replace high pressure cut-off switch as necessary Perform TEST VER-2A. If high pressure cutoff switch is okay, go to next step.
12. Check fin sensing cycling clutch switch operation. See «FIN SENSOR CYCLING CLUTCH SWITCH»(ref-205-S28802251822000030800000) in A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING. Replace fin sensing cycling clutch switch as necessary. Perform TEST VER-2A. If fin sensing cycling clutch switch is okay, go to next step.
13. Check low pressure cut-off switch. See «LOW PRESSURE CUT-OUT SWITCH»(ref-205-S18390063212000030800000) in A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING. Replace low pressure cut-off switch as necessary. Perform TEST VER-2A. If low pressure cutoff switch is okay, go to next step.
14. At this time, A/C clutch relay is assumed to be defective. Replace A/C clutch relay. Perform TEST VER-2A.

NTC-22A: CHECKING CHARGING SYSTEM

1. Ensure battery is in good condition and fully charged before proceeding with test procedure. Inspect generator belt for damage and proper adjustment. If generator belt is in good condition and properly adjusted, go to next step. If generator belt is not in good condition or not properly adjusted, repair as necessary. Perform TEST VER-3A.
2. Start engine and allow it to idle. Using scan tool, set engine speed to 2000 RPM for 30 seconds, and then return engine to idle. Using scan tool, check for DTCs. If any charging system DTCs exist, perform appropriate test for specified DTC(s) proceed to appropriate DTC test. See . If no charging system DTCs exist, go to next step.
3. Turn engine off. Turn ignition on, with engine off. Using scan tool, read and record battery voltage. Using voltmeter, check and record voltage between positive and negative battery terminals. Compare 2 voltage readings. If difference between voltage readings is one volt or more, go to next step. If difference between voltage readings is less than on volt, test is complete. Perform TEST VER-3A. NOTE: For connector terminal identification, see «CONNECTOR IDENTIFICATION»(ref-139160-S09977502222002042600000) . For circuit identification and wiring diagram, see «RAM VAN & RAM WAGON»(ref-575-S40518762292002042600000) wiring diagram in WIRING DIAGRAMS article.
4. Ensure ignition is on, with engine off. Using scan tool, actuate Generator (GEN) field driver. Using a 12-volt test light connected to ground, probe GEN field driver circuit at back of generator. Test light should cycle on and off every 1.4 seconds. While monitoring test light, wiggle wiring harness and connectors from generator to the PCM. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. If no interruption of the voltage cycle exists while wiggling wiring harness and connectors, go to next step. If interruption of the voltage cycle exists while wiggling wiring harness and connectors, repair wiring or connector where wiggling caused interruption of voltage cycle. Perform TEST VER-3A. CAUTION: Ensure all wires are clear of engine's moving parts.
5. Ensure ignition is on with engine off. Stop GEN field driver actuation. Start engine and allow it to idle. Using a voltmeter, check voltage between battery positive and generator B+ terminals. f voltage is more than .4 volt, repair B+ circuit for high resistance between generator and battery. Perform TEST VER-3A. If voltage is .4 volt or less, go to next step.
6. Turn engine off. Turn ignition on, with engine off. Using scan tool, check for DTCs. If any charging system DTCs exist, perform appropriate test for specified DTC(s) proceed to appropriate DTC test. See . If no charging system DTCs exist, go to next step.
7. Turn ignition off. Using a voltmeter, check voltage between battery negative terminal and generator case. If voltage is more than .1 volt, repair generator ground circuit for high resistance between generator case and battery. Perform TEST VER-3A. If voltage is .1 volt or less, go to next step.
8. Turn ignition on, with engine off. Using scan tool, read and record battery voltage. Turn ignition off. Disconnect PCM connectors. Clean and/or repair connectors as necessary. Turn ignition on, with engine off. Using voltmeter, check and record voltage at PCM connector B+ circuit. Compare 2 voltage readings. If difference between voltage readings is within one volt, go to next step. If difference between voltage readings is not within on volt, repair B+ circuit for high resistance between PCM and battery. Perform TEST VER-3A.
9. At this time, PCM is assumed to be defective. Replace PCM. Perform TEST VER-3A.

Final Procedure

1. Inspect vehicle to ensure all engine components are connected. Reassemble and reconnect components as necessary. Inspect engine oil for fuel contamination. Change engine oil and filter as necessary. Attempt to start engine.
2. If engine does not start, check for Technical Service Bulletins (TSBs) that apply to vehicle and return to «TEST NS-1A: QUALIFYING NO START CONDITION»(ref-139160-S39339439482002042600000) if necessary. If engine starts, repair is complete. Go to next step.
3. Turn ignition on, with engine off. Using scan tool, erase DTCs. Turn ignition off. Disconnect scan tool. Test is complete.

1. Inspect vehicle to ensure all engine components are connected. Reassemble and reconnect components as necessary. If test is being performed after performing a NO TROUBLE CODE (NTC) test, go to next step. If test is being performed after performing an OBD-II TROUBLE CODE test, perform TEST VER-5A. If test is being performed after any other TROUBLE CODE test, go to step 3).
2. Check if initial symptom still exists. If initial or another symptom exists, repair is not complete. Check for Technical Service Bulletins (TSBs) that apply to symptom and return to TEST NTC-1A: NO TROUBLE CODE TEST MENU, or appropriate TROUBLE SHOOTING - NO CODES article for diagnosis by symptom. If initial symptom no longer exists, test is complete. Go to step 8).
3. If any DTCs have not been diagnosed, perform appropriate test(s) listed under SELF-DIAGNOSTIC TESTS. See DTC MESSAGES & CODES table. If all DTCs have been diagnosed and repaired, go to next step.
4. If Powertrain Control Module (PCM) has not been replaced, use scan tool to clear DTCs from PCM. Using scan tool, reset all values in adaptive memory. To ensure no other DTCs remain, go to next step.
5. If PCM has not been replaced, and TEST VER-2A is being performed after an A/C relay control circuit DTC test, ensure A/C is on and go to next step.
6. Road test vehicle for at least 5 minutes. Road test vehicle at a speed of at least 40 MPH at some point during road test. Stop vehicle. Turn engine off for at least 10 seconds. Start engine and continue road test. Ensure transmission shifts through all gears. After road test, turn engine off and go to next step.
7. Using scan tool, read DTCs. If any DTC returns, perform appropriate test(s) listed under SELF-DIAGNOSTIC TESTS. See DTC MESSAGES & CODES table. If no DTCs return, test is complete. Go to next step.
8. Turn ignition on, with engine off. Using scan tool, erase DTCs. Turn ignition off. Disconnect scan tool. Test is complete.

1. Inspect vehicle to ensure all engine components are connected. Reassemble and reconnect components as necessary. If Powertrain Control Module (PCM) has not been replaced, use scan tool to erase DTCs. To ensure no charging system problem exists, start engine. Increase engine speed to 2000 RPM for at least 30 seconds. Allow engine to idle. Turn engine off. Turn ignition on, with engine off and go to next step.
2. Using scan tool, read DTCs. If any DTC returns, perform appropriate test(s) listed under SELF-DIAGNOSTIC TESTS. See DTC MESSAGES & CODES table. If no DTCs return, test is complete. Go to next step.
3. Turn ignition on, with engine off. Using scan tool, erase DTCs. Turn ignition off. Disconnect scan tool. Test is complete.

1. Inspect vehicle to ensure all engine components are connected. Reassemble and reconnect components as necessary. If any DTCs have not been diagnosed, return to appropriate test(s) listed under SELF-DIAGNOSTIC TESTS. See DTC MESSAGES & CODES table and finish diagnosing remaining DTCs as necessary. If all DTCs have been diagnosed and repaired, go to next step.
2. Connect scan tool to Data Link Connector (DLC) if not previously done. Ensure fuel tank is at least 1/4 full. Ensure A/C is off. Go to next step.
3. Proper way to ensure DTC is repaired is to allow Powertrain Control Module (PCM) to run monitor. Monitor operation may be observed on scan tool. All specified enabling conditions for specified DTC must be met before PCM will operate monitor. Go to next step.
4. Using scan tool, monitor pretest enabling conditions until all conditions have been met. Once all enabling conditions are met, observe appropriate monitor for DTC on scan tool. If repaired DTC has reset or the OBDII monitor failed while on road test, repair is not complete. Check for related Technical Service Bulletins (TSBs) and return to appropriate test listed under SELF-DIAGNOSTIC TESTS. See DTC MESSAGES & CODES table. If no DTCs return, test is complete. Go to step 6).
5. If another DTC exists, return to appropriate test(s) listed under SELF-DIAGNOSTIC TESTS. See DTC MESSAGES & CODES table. If no DTCs return, test is complete. Go to next step.
6. Turn ignition on, with engine off. Using scan tool, erase DTCs. Turn ignition off. Disconnect scan tool. Test is complete.

1. Inspect vehicle to ensure all engine components are connected. Reassemble and reconnect components as necessary. If any DTCs have not been diagnosed, perform appropriate test(s) listed under SELF-DIAGNOSTIC TESTS. See DTC MESSAGES & CODES table. If all DTCs have been diagnosed and repaired, go to next step. NOTE: Engine must remain at idle with shift lever in Park, and throttle at idle position when performing LDP dealer test. This test will only store a small leak DTC to indicate there is a problem with system. System failure may have been caused by a large leak, but PCM will only set small leak DTC to indicate that a failure occurred during test. NOTE: LDP DEALER TEST MODE is used when performing this test to verify repairs and check operation of leak detection pump system. When performing this test, operating mode of Powertrain Control Module (PCM) will be changed. It is critical that LDP dealer test mode not be interrupted. If LDP dealer test mode is interrupted, PCM will remain in changed mode. This will cause PCM to illuminate MIL for 8-10 miles of driving and no DTCs will be stored in PCM. Clearing DTCs from PCM will not change MIL operation. If a vehicle is found with PCM stuck in this changed mode, LDP dealer test should be performed in its entirety so proper PCM operating mode may be obtained.
2. Connect scan tool to Data Link Connector (DLC) if not previously done. Ensure all accessories are off. Start engine and allow it to idle. Ensure shift lever is in Park and throttle is in idle position. Place scan tool in LDP DEALER TEST MODE and follow instructions as displayed on scan tool. If a DTC for a small leak is set, repair is not complete. Check for related Technical Service Bulletins (TSBs) and return to DTC test from which you came. If another DTC exists, perform appropriate test(s) listed under SELF-DIAGNOSTIC TESTS. See DTC MESSAGES & CODES table. If all DTCs have been diagnosed and repaired, test is complete. Go to next step.
3. Turn ignition on, with engine off. Using scan tool, erase DTCs. Turn ignition off. Disconnect scan tool. Test is complete.

SUMMARY

If no Diagnostic Trouble Codes (DTCs) or only pass codes (system functioning properly) are found during self-diagnostics, proceed to TEST NTC-1A: NO TROUBLE CODE TEST MENU , or TROUBLE SHOOTING - NO CODES - GASOLINE article for diagnosis by symptom.