DTC P1270 Lincoln Continental IX

This DTC indicates that engine or vehicle speed has exceeded calibrated limit. Possible causes are

1. Wheel slippage caused by mud, ice, water, snow, etc.
2. Over revved engine in Neutral.
3. Vehicle driven at excessive rate of speed.

If any of the specified causes have occurred, system is okay. Clear PCM memory. If none of specified causes have occurred, clear PCM memory. Check for other driveability concerns. See TESTS W/O CODES - EEC-V article. Repair as necessary.

Diagnostic Aids

Perform this test when instructed during QUICK TEST or if directed by other test procedures. This test is used to diagnose the following

1. Standard Corporate Protocol (SCP) communication circuits BUS (+) and BUS (-).
2. Wiring harness circuits (CHASSIS GROUND, PWR GND and VBAT).
3. Faulty Powertrain Control Module (PCM).

Identifying Data Link Connector (DLC) Test Circuit & Connector Terminals. Scheme 57

Scheme 58

1. 1) Verify Self-Test Procedure Is Correct This DTC indicates «KOER ON-DEMAND SELF-TEST»(ref-131243-S21378199322001123100000) cannot be completed. Ensure scan tool is correctly attached to DLC, located under dash panel. Ensure scan tool is not damaged or defective. Ensure PTO switch/actuator is in OFF position. Verify correct procedure was used to activate self-test. Correct as necessary. If no faults are found, go to next step.
2. 2) Check VREF At Throttle Position (TP) Sensor Turn ignition off. Disconnect TP sensor. Turn ignition on. Measure voltage between SIG RTN terminal and VREF terminal at TP wiring harness connector. (Scheme 58) If voltage is 4-6 volts, go to next step. If voltage is not 4-6 volts, go to «CIRCUIT TEST C»(ref-131243-S27286541052001123100000). NOTE: KOER self-test failure or Communication Error message could result if a failure is present in MAF sensor, MLP sensor, VSS or related circuits. (Scheme 58): Identifying TP Sensor Harness Connector Terminals
3. 3) Ability To Access Continuous Memory DTCs If Continuous Memory DTCs are accessible, go to next step. If Continuous Memory DTCs are not accessible, go to step 8).
4. 4) Ability To Activate KOEO Self-Test If KOEO self-test can be activated, go to next step. If KOEO self-test cannot be activated, go to step 7).
5. 5) Ability To Activate KOER Self-Test If KOER self-test can be activated, DTC is false. Obtain PCM part number and check manufacturer for correct PCM application. If KOER self-test cannot be activated, go to step 7). NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 5) to step 7). No test procedures have been omitted.
6. 7) Retrieve Any Continuous Memory DTCs Perform «QUICK TEST»(ref-131243-S07493578722001123100000). If any DTCs are present, service as necessary before continuing. If unable to retrieve DTC, go to next step.
7. 8) Check Voltage At Data Link Connector (DLC) Inspect DLC for damage and repair as necessary. Turn ignition on. Measure voltage between B+ terminal at DLC and engine ground. If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or less, repair open in B+ circuit.
8. 9) Check DLC Ground Circuit Continuity Turn ignition off. Measure resistance between CHASSIS GROUND terminal at DLC and engine ground. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in CHASSIS GROUND circuit.
9. 10) Check DLC PWR GND Circuit Continuity Turn ignition off. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Install Breakout Box (014-00950), leaving PCM disconnected. Measure resistance between test pin No. 51 or 103 (PWR GND) at breakout box and PWR GND terminal at DLC. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in PWR GND circuit to DLC.
10. 11) Check BUS(-) Circuit Measure resistance between test pin No. 15 at breakout box and BUS(-) terminal at DLC. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in BUS(-) circuit to DLC.
11. 12) Check For Short To Ground Disconnect scan tool from DLC. Measure resistance between test pin No. 15 at the breakout box and chassis ground. If resistance is more than 10,000 ohms, go to next step. If resistance is 10,000 ohms or less, repair short to ground in BUS(-) circuit.
12. 13) Check For Short To Power Turn ignition on. Measure voltage between test pins No. 15 and 51 or 103 (PWR GND) at the breakout box. If voltage is 6 volts or less, go to next step. If voltage is more than 6 volts, repair short to power in BUS(-) circuit.
13. 14) Check BUS(+) Circuit Continuity Turn ignition off. Measure resistance between test pin No. 16 (BUS+) at the breakout box and chassis ground. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in BUS(+) circuit to DLC.
14. 15) Check BUS(+) Circuit For Short To Ground Measure resistance between chassis ground and test pin No. 16 (BUS+) at breakout box. If resistance is more than 10,000 ohms, go to next step. If resistance is 10,000 ohms or less, repair short to ground in BUS(+) circuit.
15. 16) Check BUS(+) Circuit For Short To Power Turn ignition on. Measure voltage between test pins No. 16 and 51 or 103 (PWR GND) at breakout box. If voltage is one volt or less, go to next step. If voltage is more than one volt, repair short to power in BUS(+) circuit.
16. 17) Power Take Off (PTO) Applications If vehicle is equipped with PTO, go to next step. If vehicle is not equipped with PTO, replace PCM.
17. 18) Check PTO On/Off Input Turn ignition on. While toggling PTO switch/actuator switch, measure voltage between test pins No. 4 (PTO) and 51 or 103 (PWR GND) at breakout box. If voltage is less than one volt with PTO off, and more than one volt with PTO on, PTO circuit is okay. Replace PCM. If voltage is not as specified, go to «CIRCUIT TEST FB»(ref-131243-S24525434152001123100000).