8 - ND - DODGE DAKOTA -.7L MAGNUM V8 P-O SENSOR / HEATER CIRCUIT HIGH S6 K9 BR/DG - LEFT FRONT K99 Z K K9 8 8 BR/TN BK/LB DB/LB BR/DG G8 8 C C C O / O / O RETURN HEATER SIGNAL (UPSTREAM) CONTROL CONTROL BLACK/BLACK BLACK/BLACK 8 9 8 9 CONTROL C (.7L) BLACK/ORANGE CONTROL C (.7L) BLACK/ORANGE - LEFT FRONT (.7L) - LEFT FRONT (.7L) 8 9 8 9 CONTROL C (.7L) CONTROL C (.7L) 8af For a complete wiring diagram, refer to the Wiring Information. When Monitored: Continuously during O heater operation with battery voltage between. and 5.75 volts. Set Condition:
The PCM detects that the O sensor heater element input is above the maximum acceptable voltage. One trip fault. Three good trips to turn off the MIL. Possible Causes (K99) O / HEATER CONTROL CIRCUIT OPEN (Z) O / HEATER GROUND CIRCUIT OPEN (K99) O / HEATER CONTROL CIRCUIT SHORTED TO VOLTAGE / O SENSOR CONTROL MODULE (PCM) Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 8 - DTC-Based Diagnostics/. ACTIVE DTC 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 can result possible serious or fatal injury. If P688-AUTO SHUTDOWN RELAY SENSE CIRCUIT LOW has set along with any of the O SENSOR HEATER CIRCUIT HIGH DTCs, all of the O Sensor Heater Control circuits need to be checked for a short to battery voltage.. Start the engine and allow it to idle for at least 6 seconds.. With a scan tool, select View DTCs. Is the DTC Active at this time? Yes Go To No Perform the INTERMITTENT CONDITION diagnostic procedure. (Refer to 8 - DTC-Based Diagnostics/. O HEATER ELEMENT. Turn the ignition off. Allow the O Sensor to cool down to room temperature.. Disconnect the / O Sensor harness connector.. Measure the resistance across the O Sensor Heater element between the O Heater Control terminal and the O Heater ground terminal at the component. O Heater Element resistance values should be measured at. C (7 F). The resistance value will vary with different temperature values. Is the O Sensor Heater Element resistance between. and. Ohms? Yes Go To No Replace the O Sensor.
Perform VERIFICATION TEST. (Refer to 8 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) -. (K99) O / HEATER CONTROL CIRCUIT. Ignition on, engine not running.. Using a -volt test light connected to ground, probe the (K99) O / Heater Control circuit in the O Sensor harness connector. Make sure the test light is probing the circuit before actuating the Heater Test or a DTC may set and not allow the actuation.. With a scan tool, actuate the O / Heater Test with the O Sensor harness connector still disconnected. The test light should be illuminated and bright proportional to the maximum duty cycle allowed by the scan tool. For example, if the scan tool allows % actuation, the brightness should be as bright as a direct connection to the battery. If the scan tool allows a maximum 5% actuation, the brightness should be 5% as bright as a direct connection to the battery. 57 Does the test light illuminate brightly and flash on and off during the actuation? Yes Go To No Go To 5
. (Z) O HEATER GROUND CIRCUIT OPEN. Turn the ignition off.. Measure the resistance between an engine ground and the (Z) O / Heater ground circuit in the O Sensor harness connector. Is the resistance below 5. Ohms? Yes Replace the O Sensor. Perform VERIFICATION TEST. (Refer to 8 - DTC-Based Diagnostics/ No Repair the open in the (Z) O / Heater ground circuit. Perform VERIFICATION TEST. (Refer to 8 - DTC-Based Diagnostics/ 59 5. (K99) O / HEATER CONTROL CIRCUIT SHORTED TO VOLTAGE. Turn the ignition off.. Disconnect the C PCM harness connector.. Ignition on, engine not running.. Measure the voltage of the (K99) O / Heater Control circuit in the / Oxygen Sensor harness connector. Is there any voltage present? V Yes Repair the short to voltage in the (K99) O / Heater Control circuit. Perform VERIFICATION TEST. (Refer to 8 - DTC-Based Diagnostics/ No Go To 6 5
6. (K99) O / HEATER CONTROL CIRCUIT OPEN. Turn the ignition off. CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the PCM Pinout Box Kit, NGC, 8 Position 885A to perform diagnosis. 8. Measure the resistance of the (K99) O / Heater Control circuit from the O Sensor harness connector to the appropriate terminal of PCM Pinout Box 885A. Is the resistance below 5. Ohms? Yes Go To 7 9 6 8 5 8 No Repair the open in the (K99) O / Heater Control circuit. Perform VERIFICATION TEST. (Refer to 8 - DTC-Based Diagnostics/ PCM PINOUT BOX 885 5 7. CONTROL MODULE (PCM). Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Oxygen Sensor / and the Powertrain Control Module (PCM).. 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 / O Sensor and Powertrain Control Module connectors.. Perform any Technical Service Bulletins that may apply. Were there any problems found? Yes Repair as necessary. Perform VERIFICATION TEST. (Refer to 8 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - No Replace and program the Powertrain Control Module in accordance with the Service Information. Perform VERIFICATION TEST. (Refer to 8 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - 5