Diagnostic Tools
Below is an equipment list with corresponding part numbers
REQUIRED EQUIPMENT
- Rotunda Worldwide Diagnostic System (WDS), Vehicle Communication Module (VCM) with appropriate adaptors or equivalent diagnostic tool with functionality described under Diagnostic Tool Setup and Functionality.
- Rotunda Smoke Machine, Fuel Evaporative Emission System Tester 218-00001 (522) or equivalent.
RECOMMENDED EQUIPMENT
- Rotunda EEC-V 104-Pin Breakout Box 418-049 (014-00950) or equivalent.
- Rotunda Vacuum/Pressure Tester 164-R0253 or equivalent. Range 0-101.3 kPa (0-30 in-Hg.) Resolution 3.4 kPa (1 in-Hg.)
- Rotunda Vacuum Tester 014-R1054 or equivalent. Range 0-101.3 kPa (0-30 in-Hg.)
- Rotunda 73III Automotive Meter 105-R0057 or equivalent. Input impedance 10 Megaohm minimum.
- Spark Tester D81P-6666-A (303-D037) or equivalent.
- Non-powered test lamp.
OPTIONAL EQUIPMENT
- Rotunda Fuel (Gasoline) pressure test kit 134-R0087 or equivalent. (Use tool manufacturer's instructions.)
Diagnostic Tool Setup and Functionality
The diagnostic tool must be connected to the data link connector (DLC) for communication with the vehicle.
The DLC is located in the passenger compartment. It is attached to the instrument panel and accessible from the driver seat.
The DLC is rectangular in design and capable of accommodating up to 16 terminals. The connector has keying features to allow easy connection. The DLC connector and the diagnostic tool connector have latching features that make sure the diagnostic tool connector will remain mated when properly connected.
The required diagnostic tool functions are described below
- Monitor, record, and playback of PIDs
- Freeze frame PID data
- Diagnostic test modes; self-test, clear diagnostic trouble codes (DTCs)
- Output test mode
- Resetting keep alive memory (KAM)
- Diagnostic monitoring test results for on-board diagnostic (OBD) on-board monitors
- On-board system readiness (OBD monitor completion status)
Some of these functions are described in this article. Refer to the diagnostic tool manufacturer's manual for specific information on diagnostic tool setup and operation.
Quick Test
The Quick Test is divided into three specialized tests
- Key On Engine Off (KOEO) On-Demand Self-Test
- Key On Engine Running (KOER) On-Demand Self-Test
- Continuous Memory Self-Test
The Quick Test checks the integrity and function of the electronic engine control (EEC) system and outputs the test results when requested by a diagnostic tool. The Quick Test also provides a quick end check of the powertrain control system, and is usually carried out at the start of each diagnostic procedure with all accessories off. The Quick Test is also carried out at the end of most pinpoint tests for verification of the repair and to make sure no other faults are incurred while repairing a previous fault. A system pass will be displayed when no diagnostic trouble codes (DTCs) are output and a diagnostic tool communication error does not exist. System pass means that hardware monitored by the powertrain control module (PCM) is functioning within the normal operating limits. Only a system pass, a DTC, or an incomplete on-board diagnostic (OBD) drive cycle (P1000) will be displayed.
For applications that use a stand-alone transmission control module (TCM) the PCM will not output TCM DTCs. For TCM self-test and diagnostics, refer to AUTOMATIC TRANSMISSION .
Key On Engine Off (KOEO) On-Demand Self-Test
The KOEO on-demand self-test is a functional test of the powertrain control module (PCM) carried out on-demand with the key on and the engine off. This test will carry out checks on certain sensor and actuator circuits. A fault must be present at the time of testing for the KOEO self-test to detect the fault. When a fault is detected, a DTC is output on the data link at the end of the test as requested by a diagnostic tool.
Key On Engine Running (KOER) On-Demand Self-Test
The KOER on-demand self-test is a functional test of the PCM carried out on-demand with the key on, the engine running and the vehicle stopped. A check of certain inputs and outputs is made during operating conditions and at a normal operating temperature. The brake pedal position, transmission control, and power steering tests are part of the KOER on-demand self-test and must be carried out during this operation if applicable. These are described below. A fault must be present at the time of testing for the KOER on-demand self-test to detect the fault. When a fault is detected, a DTC is output on the data link at the end of the test as requested by a diagnostic tool.
Brake Pedal Position (BPP) Test
This tests the ability of the EEC system to detect a change of state in the BPP switch. The brake pedal is briefly applied and released on all vehicles equipped with a BPP input. This is done during a KOER on demand self-test.
Transmission Control Switch (TCS) Test
This tests the ability of the EEC system to detect a change of state in the TCS. The switch is briefly cycled on all vehicles equipped with a TCS input. This is done during a KOER on-demand self-test.
Power Steering Pressure (PSP) Test
This tests the ability of the EEC system to detect a change in the power steering system fluid pressure. The steering wheel is briefly turned at least 1/4 of a revolution on vehicles equipped with a PSP switch or sensor. This is done during a KOER on-demand self-test.
Continuous Memory Self-Test
The continuous memory self-test is a functional test of the PCM carried out under any condition (engine running or off) with the key on. Unlike the KOEO and KOER self-tests, which can only be activated on-demand, the continuous self-test is always active. A fault does not need to be present when accessing continuous memory self-test DTCs, making the test valuable when diagnosing intermittent faults. The vehicle may need to be driven or the on-board diagnostic (OBD) drive cycle completed to allow the PCM to detect a fault. Refer to ON BOARD DIAGNOSTIC (OBD) DRIVE CYCLE for more information. When a fault is stored in memory, a DTC will be output on the data link at the end of the test when requested by a diagnostic tool.
There are two types of continuous DTCs. The first type is an emission-related malfunction indicator lamp (MIL) code which will illuminate the CHECK ENGINE or SERVICE ENGINE SOON indicator in the instrument cluster. The second is a non-emission related, non-MIL code which will not illuminate the cluster indicator.
For emission-related MIL codes, the PCM stores the DTC in continuous memory when a fault is detected for the first time. At this point the DTC does not illuminate the MIL and is now considered a pending code. The purpose of pending codes is to assist in repair verification by reporting a pending DTC after one drive cycle. If the same fault is detected after the next ignition start-run cycle, the emission-related MIL code illuminates the MIL. The MIL remains on even if the fault is intermittent. The MIL is extinguished if the fault is not present through 3 consecutive drive cycles or the DTCs are cleared. Also, an emission-related pending MIL and non-emission related (non-MIL) DTCs are erased after approximately 40 vehicle warm up cycles or the DTCs are cleared.
Any diagnostic tool that meets OBD requirements can access the continuous memory to retrieve emission-related MIL DTCs. However, not all diagnostic tools access pending and non-emission related (non-MIL) DTCs in the same way.
During most diagnostic procedures in this article, it is required that all DTCs be retrieved and cleared. Consult the instruction manual from the tool manufacturer for specific instructions.
Diagnostic Monitoring Test Results
The purpose of this test mode is to allow access to the results of OBD monitor diagnostic test results. The test values that are stored at the time of the particular monitor completion are displayed when the particular test identification is requested. Refer to DIAGNOSTIC MONITORING TEST RESULTS table for test information.
| Module ID h (1) | Test ID h (1) | Component ID h (1) | Test Description |
|---|---|---|---|
| Oxygen Sensor Monitor (01-0F) | |||
| 10 | 01 | 11 | Sensor Voltage Amplitude - Bank 1, Sensor 1 |
| 10 | 01 | 21 | Sensor Voltage Amplitude - Bank 2, Sensor 1 |
| 10 | 02 | 11 | Upstream Static Shift, Lean Shift on HO2S11 |
| 10 | 02 | 11 | Upstream Static Shift, Rich Shift on HO2S11 |
| 10 | 02 | 21 | Upstream Static Shift, Lean Shift on HO2S21 |
| 10 | 02 | 21 | Upstream Static Shift, Rich Shift on HO2S21 |
| 10 | 03 | 01 | Upstream Switchpoint |
| 10 | 03 | 02 | Downstream Switchpoint |
| Catalyst Monitor (10-1F) | |||
| 10 | 10 | 11 | Rear to Front Switch Ratio Test - Bank 1 test |
| 10 | 10 | 21 | Rear to Front Switch Ratio Test - Bank 2 test |
| Evaporative Monitor (21-2F) | |||
| 10 | 21 (2) | 00 | Fuel Tank Pressure Test - Low |
| 10 | 21 (2) | 00 | Fuel Tank Pressure Test - High |
| 10 | 22 (2) | 00 | Evap-Phase 2 Change in Pressure Test |
| 10 | 23 (2) | 00 | Evap-Phase 4 Change in Pressure too Large |
| 10 | 24 (2) | 00 | Evap-Phase 4 Change in Pressure too Small |
| 10 | 25 (2) | 00 | Evap-Phase 4 Pressure Build Test-Upper Limit |
| 10 | 26 | 00 | Phase 0 Initial Tank Vacuum and Minimum Limit |
| 10 | 26 | 00 | Phase 0 Initial Tank Vacuum and Maximum Limit |
| 10 | 27 | 00 | Phase 2 0.040" Cruise Leak Check Vacuum Bleed-up and Max 0.04" Leak Threshold |
| 10 | 28 | 00 | Phase 2 0.020" Cruise Leak Check Vacuum Bleed-up and Max Leak Threshold |
| 10 | 29 | 00 | EVAP-Phase 4 Change in Pressure too Small |
| 10 | 2A | 00 | Phase 4 Vapor Generation Maximum Change in Pressure and Maximum Threshold |
| 10 | 2B | 00 | Phase 4 Vapor Generation Maximum Absolute Pressure Rise and Maximum Threshold |
| 10 | 2C | 00 | Phase 2 0.020" Idle Leak Check Vacuum Bleed-up and Max Leak Threshold |
| 10 | 2D | 00 | Phase 2 0.020" Idle Leak Check Vacuum Bleed-up and Max No-leak threshold |
| Secondary Air Monitor (30-3F) | |||
| 10 | 30 | 11 | HO2S11 Rich During Flow Test |
| 10 | 30 | 21 | HO2S21 Rich During Flow Test |
| 10 | 30 | 12 | HO2S12 Rich During Flow Test |
| 10 | 31 | 00 | HO2S Lean Timer Test |
| 10 | 31 | 01 | HO2S Lean Timer Test |
| EGR System Monitor (41-4F) | |||
| 10 | 41 (2) | 11 | Upstream Hose Disconnected Test |
| 10 | 41 (2) | 12 | Downstream Hose Disconnected Test |
| 10 | 45 | 20 | Stuck Open Valve Test |
| 10 | 49 | 30 | EGR Flow Test |
| 10 | 4B | 30 | Flow Test |
| Misfire Monitor (51-5F) | |||
| 10 | 50 | 00 | Total Misfires That Exceeded Threshold |
| 10 | 53 | 01 | Misfire Rate per 200 revs for Cylinder 1/Type A |
| 10 | 53 | 02 | Misfire Rate per 200 revs for Cylinder 2/Type A |
| 10 | 53 | 03 | Misfire Rate per 200 revs for Cylinder 3/Type A |
| 10 | 53 | 04 | Misfire Rate per 200 revs for Cylinder 4/Type A |
| 10 | 53 | 05 | Misfire Rate per 200 revs for Cylinder 5/Type A |
| 10 | 53 | 06 | Misfire Rate per 200 revs for Cylinder 6/Type A |
| 10 | 53 | 07 | Misfire Rate per 200 revs for Cylinder 7/Type A |
| 10 | 53 | 08 | Misfire Rate per 200 revs for Cylinder 8/Type A |
| 10 | 53 | 09 | Misfire Rate per 200 revs for Cylinder 9/Type A |
| 10 | 53 | 0A | Misfire Rate per 200 revs for Cylinder 10/Type A |
| 10 | 54 | 00 | Highest Misfire Rate in 200 rev test/Type A |
| 10 | 55 | 00 | Highest Misfire Rate in 1000 rev test/Type B |
| 10 | 56 | 00 | Misfire Monitor Trip complete test |
| (1) = hexadecimal (2) = These test IDs are signed values. The diagnostic tool may display them as unsigned. | |||
| (1) | = hexadecimal |
| (2) | = These test IDs are signed values. The diagnostic tool may display them as unsigned. |
DIAGNOSTIC MONITORING TEST RESULTS
The conversion is done as follows
If the value is > 32767 then complement (change 0's to 1's and 1's to 0's), add 1 and a negative sign.
Example
| 50000 = | 1100001101010000 |
|---|---|
| Complement of 50000 = | 0011110010101111 |
| +1 | |
| 0011110010110000 | |
| Signed Value = | 15536 |
CONVERSION
Intermittent Diagnostic Techniques
Intermittent diagnostic techniques help find and isolate the root cause of intermittent faults associated with the electronic engine control (EEC) system. The information is organized to help find the fault and carry out the repair. The process of finding and isolating an intermittent starts with recreating a fault symptom, accumulating PCM data, and comparing that data to typical values, then analyzing the results. Refer to the diagnostic tool user manual for the functions described below.
Before proceeding, be sure that
- Customary mechanical system tests and inspections do not reveal a concern. NOTE: Mechanical component conditions can make a PCM system react abnormally.
- Technical Service Bulletins (TSBs), if available, are reviewed.
- Quick Test and associated diagnostic subroutines have been completed without finding a fault, and the symptom is still present.
Adaptive Fuel Diagnostic Trouble Codes Diagnostic Techniques
| DTC | Description |
|---|---|
| DTC P0171/P0174 | System Too Lean Diagnostic Aids |
| DTC P0172/P0175 | System Too Rich Diagnostic Aids |
DIAGNOSTIC TROUBLE CODES (DTC) LIST
The Adaptive Fuel DTC Diagnostic Techniques help isolate the root cause of the adaptive fuel concern. Before proceeding, attempt to verify if any driveability concerns are present. These diagnostic aids are meant as a supplement to the Pinpoint Test. For a description of fuel trim, refer to FUEL TRIM .