Pinpoint Test
NOTE:
Make sure battery voltage is greater than 12.2 volts prior to and during this pinpoint test.
NOTE:
Do not have a battery charger attached during vehicle testing.
- CHECK THE BATTERY CONDITION
- Carry out Battery Condition Test to determine if the battery can hold a charge and is OK for use. REFER to DIAGNOSTIC ROUTINE A .
- Does the battery pass the condition test?
- Yes: GO to step 2 .
- No: INSTALL a new battery. REFER to BATTERY .
- Carry out Battery Condition Test to determine if the battery can hold a charge and is OK for use. REFER to DIAGNOSTIC ROUTINE A .
- CHECK THE GENERATOR CONNECTIONS
- Ignition OFF.
- Disconnect and inspect all generator connectors.
- Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary
- Connect the generator connectors. Make sure they seat, latch correctly and are tightened to specification. REFER to TORQUE SPECIFICATIONS .
- Measure and record battery voltage at the battery.
- Measure:
- Is the voltage within 0.5 volt of recorded battery voltage?
- Yes: GO to step 3 .
- No: VERIFY the fusible links are OK. If OK, REPAIR the circuit. If not OK, REFER to the SYSTEM WIRING DIAGRAMS to identify the possible causes of the circuit short.
- CHECK THE VOLTAGE DROP IN THE B+ CIRCUIT
- Start the engine.
- With the engine running at idle, headlamps on and blower on high, measure:
- Carry out a wiggle test of the generator wiring and connections while measuring voltage drop.
- Is the voltage drop less than 0.5 volt?
- Yes: GO to step 4 .
- No: INSPECT and REPAIR any corrosion in the generator B+ circuit or positive battery cable connections.
- "A" SENSE CIRCUIT LOAD TESTNOTE: The following step uses a test light to simulate normal circuit loads. Use only the test light recommended in the Special Tools table at the beginning of this section. To avoid connector terminal damage, use the Flex Probe Kit for the test light probe connection to the vehicle. Do not use the test light probe directly on any connector.NOTE: This step puts a load on the "A" sense circuit. If there are corroded or loose connections, loading the circuit may help show the fault. A 250-350 mA incandescent 12-volt test lamp is required for this step. This circuit will not be loaded properly using an Light-emitting Diode (LED)-style test lamp.
- Ignition OFF.
- Disconnect: Generator C102A.
- Ignition ON.
- Using a 12-volt test lamp, check for voltage:
- Does the test lamp illuminate?
- Yes: GO to step 5 .
- No: VERIFY Battery Junction Box (BJB) fuse 58 (10A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the SYSTEM WIRING DIAGRAMS to identify the possible causes of the circuit short.
- CHECK THE GENERATOR COMMAND CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Powertrain Control Module (PCM) C175B.
- Ignition ON.
- Measure:
- Is any voltage present?
- Yes: REPAIR the circuit.
- No: GO to step 6 .
- CHECK THE GENERATOR COMMAND CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Measure:
- Is the resistance greater than 10,000 ohms?
- Yes: GO to step 7 .
- No: REPAIR the circuit.
- CHECK THE GENERATOR COMMAND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Measure:
- Is the resistance less than 3 ohms?
- Yes: GO to step 8 .
- No: REPAIR the circuit.
- COMPARE THE GENERATOR MONITOR (GENMON) AND GENERATOR COMMAND (GENCMD) Parameter Identifications (PIDs)
- Ignition OFF.
- Connect: Powertrain Control Module (PCM) C175B.
- Connect a fused jumper wire:
- Start the engine.
- Using a scan tool, view the Powertrain Control Module (PCM) Parameter Identifications (PIDs).
- Monitor the Powertrain Control Module (PCM) Parameter Identifications (PIDs) GENMON and GENCMD while performing a wiggle test on the generator harness.
- Do the Parameter Identifications (PIDs) read within 5% of each other?
- Yes:
REMOVE the fused jumper wire.
INSTALL a new generator. REFER to GENERATOR - 3.5L TI-VCT .
- No:
REMOVE the fused jumper wire.
GO to step 9 .
- CHECK FOR CORRECT Powertrain Control Module (PCM) OPERATION
- Ignition OFF.
- Disconnect and inspect all Powertrain Control Module (PCM) connectors.
- Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary
- Reconnect the Powertrain Control Module (PCM) and generator connectors. Make sure they seat and latch correctly.
- Operate the system and determine if the concern is still present.
- Is the concern still present?
- Yes: CHECK On-Line Automotive Service Information System (OASIS) for any applicable Technical Service Bulletins (TSBs). If a Technical Service Bulletin (TSB) exists for this concern, DISCONTINUE this test and FOLLOW the Technical Service Bulletin (TSB) instructions. If no Technical Service Bulletin (TSB) address this concern, INSTALL a new Powertrain Control Module (PCM). REFER to POWERTRAIN CONTROL MODULE (PCM) .
- No: The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.