Engine Controls - Tests W/codes - 2.5L: Diagnosis Dodge Dakota Sport

SYSTEM DIAGNOSIS

The self-diagnostic capabilities of this system, if properly utilized, can simplify testing. The Single-Board Engine Controller (SBEC) monitors several different engine control system circuits.

If a problem is sensed with a monitored circuit, a fault code is stored in the SBEC, the CHECK ENGINE light illuminates, and SBEC enters limp-in mode. In limp-in mode, SBEC compensates for component failure by substituting information from other sources. This allows vehicle operation until repairs can be made.

Once fault codes are known, refer to FAULT CODES table in this article to determine the questionable circuit. Test circuits and repair or replace components as required. If problem is repaired or ceases to exist, the SBEC cancels that fault code after approximately 50 ignition on-off cycles. To clear fault codes, see CLEARING FAULT CODES in this article.

A specific fault code is the result of a particular system failure, but it DOES NOT indicate that cause of failure is necessarily within system. The fault code DOES NOT condemn any specific component; it pinpoints a probable malfunctioning area.

DIAGNOSTIC PROCEDURE

To obtain fault codes, see RETRIEVING FAULT CODES in this article. If fault codes are NOT present and/or Diagnostic Readout Box II (DRB-II) is used, proceed to one of the following tests.

1. Go to NO START TEST 1A (NS-1A) chart if a no-start condition exists, or engine stalls after start-up. Perform indicated VERIFICATION PROCEDURE chart after repairs. Ensure charts apply to engine being tested.
2. Go to DRIVEABILITY TEST 1A (DR-1A) chart if engine runs but has performance problems. Perform indicated VERIFICATION PROCEDURE chart after repairs. Ensure charts apply to engine being tested.

Note. When using trouble shooting charts for diagnosis, DO NOT skip any steps in chart, or incorrect diagnosis may result.

Before proceeding with diagnosis, the following precautions must be followed

1. Vehicle must have a fully charged battery, and functional charging system.
2. Probe SBEC connector from pin side. DO NOT backprobe SBEC connector.
3. DO NOT cause short circuits when performing electrical tests. This will set additional fault codes, making diagnosis of original problem more difficult.
4. DO NOT use a test light in place of a voltmeter.
5. When checking for spark, ensure coil wire is NO more than 1/4" from ground. If coil wire is more than 1/4" from ground, damage to vehicle electronics and/or SBEC may result.
6. DO NOT prolong testing of fuel injectors, or engine may hydrostatically (liquid) lock.
7. Always repair lowest fault code number (CHECK ENGINE light), or first fault displayed (DRB-II) first.
8. Always perform VERIFICATION PROCEDURE test after repairs are made.
9. Always disconnect DRB-II after use.
10. Always disconnect DRB-II before charging battery.

ACTUATOR TEST MODE

Actuator test mode is used to check operation of output circuits of devices the SBEC cannot recognize. The following, depending on engine and model application, can be activated in actuator test mode to ensure component operation: relays, solenoids and various components. The following are information or components that may be accessed through actuator test mode.

1. A/C Clutch Relay
2. Air Idle Speed (AIS) Motor
3. Air Switch Solenoid
4. Alternator Field
5. ASD (Auto Shutdown) Relay
6. ASD (Auto Shutdown) System
7. CHECK ENGINE Light
8. EGR Solenoid
9. Emission Maintenance Reminder (EMR) Light
10. Fuel Injector
11. Ignition Coil
12. Overdrive Solenoid
13. Part Throttle Unlock (PTU) A/T Only
14. Purge Solenoid
15. Radiator Fan Relay
16. Shift Indicator Light (M/T Only)
17. Solenoid/Relays
18. Speed Control Servo Solenoids
19. Stop All Tests
20. Tachometer Output

KEYPAD TEST FAILURE

Ensure ignition is off. DO NOT touch keypad on DRB-II. Turn ignition on. If DRB-II displays KEYPAD TEST FAILURE, replace DRB-II. If KEYPAD TEST FAILURE message is not displayed, proceed with diagnostics.

RAM TEST FAILURE

If message is displayed, replace DRB-II and proceed with diagnostics.

TROUBLE SHOOTING CHARTS

Note. The following trouble shooting charts and illustrations are courtesy of Chrysler Motors.

NO START DIAGNOSTIC FLOW CHARTS: NS-1A TO NS-17A

Note. The following trouble shooting charts and illustrations are courtesy of Chrysler Motors.

Test NS-1A: Ignition Spark & Power Feed To Coil Ckt Diag. Scheme 8

Test NS-1A: (1 of 3) Ignition Spark & Power Feed To Coil. Scheme 9

Test NS-1A: (2 of 3) Ignition Spark & Power Feed To Coil. Scheme 10

Test NS-1A: (3 of 3) Ignition Spark & Power Feed To Coil. Scheme 11

Test NS-2A: (1 of 2) Fuel Spray & Fault Messages With DRB-II. Scheme 12

Test NS-2A: (2 of 2) Fuel Spray & Fault Messages With DRB-II. Scheme 13

Test NS-3A Ckt Diag: Injector Faults, Power To SBEC, MAP Sensor & Theft status. Scheme 14

Test NS-3A: (1 of 3) Injector Faults, Power To SBEC, MAP Sensor & Theft status. Scheme 15

Test NS-3A: (2 of 3) Injector Faults, Power To SBEC, MAP Sensor & Theft status. Scheme 16

Test NS-3A: (3 of 3) Injector Faults, Power To SBEC, MAP Sensor & Theft status. Scheme 17

NS-17A: PERFORMING NO FAULT CODE MECHANICAL TEST

At this point in the start-and-stall test procedure, if it is determined that all engine control systems are operating as designed and are not the cause of a no start-and-stall problem, the following additional items should be checked as possible causes

1. Check if any TECHNICAL SERVICE BULLETINS (TSBs) apply to vehicle.
2. Check engine vacuum.
3. Check engine compression.
4. Check for exhaust system restriction.
5. Check camshaft and crankshaft sprockets.
6. Check valve timing.
7. Check torque converter stall speed.
8. Check secondary ignition circuit for abnormal scope pattern.
9. Check for fuel contamination.
10. Ensure PCV system is functioning properly.

DRIVEABILITY DIAGNOSTIC FLOW CHARTS DR-1A TO DR-45A

Note. The following trouble shooting charts and illustrations are courtesy of Chrysler Motors.

DR-41A: PERFORMING NO FAULT CODE MECHANICAL TEST

At this point in the driveability test procedure, if it is determined that all engine control systems are operating as designed and are not the cause of driveability problem, check the following additional items for possible causes

1. Check valve timing.
2. Check torque converter stall speed.
3. Check engine compression.
4. Check camshaft and crankshaft sprockets.
5. Check for internal power brake booster vacuum leaks.
6. Check for fuel contamination.
7. Check for exhaust system restriction.
8. Ensure injectors are not plugged or restricted.
9. Ensure injector control wire is connected to correct injector.
10. Ensure engine vacuum is at least 13 in. Hg.
11. Ensure PCV system is functioning properly.

Test DR-42A: Intermittent Test For Solenoids & Relays. Scheme 18

Test DR-43A: Intermittent Voltage Sensor. Scheme 19

Test DR-43B: Intermittent Test For MAP Sensor Signal Change. Scheme 20

Test DR-44A: Intermittent Test For Idle Motor Circuits. Scheme 21

Test DR-45A: Intermittent Test For Injector Circuits. Scheme 22