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Engine Controls - Tests W/codes - 4.0L: Diagnosis Jeep Cherokee II

SELF-DIAGNOSTIC SYSTEM

ModelBody Code
Cherokee & WagoneerXJ
ComancheMJ

BODY CODE EXPLANATION

DIAGNOSIS & SYSTEM TESTING

  1. This is an interactive functional test of a particular system. During testing, DRB-II will provide instructions to technician. After task is performed, press ENTER key. A fault will be generated since the technician has performed a requested action and tester had not seen any indication from the diagnostic pins.
  2. Some tests such as engine coolant temperature sensor require longer periods before the circuit is automatically faulted (depending on ambient temperature).
  3. If a correct operating condition is not seen within a preprogrammed amount of time, the DRB-II keyboard is locked out. If there is a circuit problem, the test must time-out (the ENTER key cannot be used to force an error condition).
  4. After performing a SYSTEM TEST, if the DRB-II was unable to detect a fault with the system, the DRB-II will display VEHICLE PASSES ELECTRICAL TEST.
  5. One of the following alpha characters may appear as a prefix to a fault code. The character displayed can be used as an indication of where in the engine test sequence the fault was detected. Alpha prefixes are displayed only during a SYSTEM TEST. "A" (First Key Off) - Ignition switch in the OFF position. "B" (Key On Before Fuel Pump Drops Out) - Ignition switch in the ON position. Fuel Pump Drops Out refers to fuel pump relay being activated by the ECU and fuel pump being activated. If the ECU does not detect a crank signal within a few seconds after ignition is turned on, the ECU will automatically open ground circuit to fuel pump relay. This will disable fuel pump. "C" (Key On After Fuel Pump Drops Out) - Ignition switch is in the ON position after fuel pump relay has timed out (fuel pump off). "D" (First Crank) - The engine is cranking but not running. "E" (First Engine Start) - Engine idling. "F" (Second Key Off Before Fuel Pump Drops Out) - Ignition switch is in the OFF position for the second time before fuel pump relay has timed out. "G" (Second Key Off After Fuel Pump Drops Out) - Ignition switch is in the OFF position for the second time before fuel pump relay has timed out. "G" (Second Key On) - No text. "I" (Second Engine Start) - No text. "J" (Last Key Off) - No text. "X" (ECU Defined Faults) - Faults detected by ECU on-board diagnostics.

DIAGNOSTIC TROUBLE CODE (DTC) MENU

DTCFault Condition
1000Ignition Line Low.
1001Ignition Line High.
1002O2 Heater Low Line.
1004Battery Voltage Low.
1005Sensor Ground Line Out Of Limits.
1013MPA Line High.
1014Fuel Pump Line Low.
1015Fuel Pump Line High.
1016MAT Sensor Line Low.
1017MAT Sensor Line High.
1018No Serial Data.
1020No Sync Pulse Seen.
1021Engine Failed To Start Due To Mechanical, Fuel Or Ignition Problem.
1022Start Line Low.
1027ECU Sees Wide Open Throttle.
1028ECU Does Not See Wide Open Throttle.
1031ECU Sees Closed Throttle.
1032ECU Does Not See Closed Throttle.
1037TPS Circuit Reads Low.
1038Park/Neutral Line High (A/T).
1039Park/Neutral Line Low (A/T).
1040Latched B+ Line Low.
1041Latched B+ Line High.
1042No Latched B+ 1/2 Volt Drop.
1044Fault In Shift Light Circuit (M/T).
1047Wrong ECU.
1048Manual Vehicle Equipped With Automatic ECU.
1049Automatic Transmission Vehicle Configuration.
1050Idle RPM Less Than 500.
1051Idle RPM Greater Than 2000.
1052MAP Sensor Out Of Limits.
1053Change In Map Reading Out Of Limits.
1054Coolant Temperature Sensor Line Low.
1055Coolant Temperature Sensor Line High.
1056Inactive Coolant Temperature Sensor.
1057Knock Circuit Shorted.
1058Knock Value Out Of Limits.
1059A/C Request Circuit Low.
1060A/C Request Circuit High.
1061A/C Select Circuit Low.
1062A/C Select Circuit High.
1063A/C Clutch Circuit Low.
1064A/C Clutch Circuit High.
1065O2 Sensor Reads Rich.
1066O2 Sensor Reads Lean.
1067Latch Relay Circuit Low.
1068Latch Relay Circuit High.
1069No tach.
1073ECU Does Not See Speed Sensor.
1200Defective ECU Or Short To Voltage.
1201Injector Short To B+.
1202All Injectors Shorted To Ground.
1203Injector #1 Shorted To Ground.
1204Injector #2 Shorted To Ground.
1205Injector #3 Shorted To Ground.
1206Injector #4 Shorted To Ground.
1207Injector #5 Shorted To Ground.
1208Injector #6 Shorted To Ground.
1209All Injectors Open.
1210Injector #1 Circuit Open.
1211Injector #2 Circuit Open.
1212Injector #3 Circuit Open.
1213Injector #4 Circuit Open.
1214Injector #5 Circuit Open.
1215Injector #6 Circuit Open.
1216No Voltage At ECU From A/C Relay.
1217No Voltage At ECU From O2 Heater Relay.
1218No Voltage At ECU From Power Latch Relay.
1219No Voltage At ECU From Shift Light.
1220No Voltage At ECU From EGR Solenoid.
1222MPA Not Grounded.
1223Checking For Open Injector Feed Circuits

DTC IDENTIFICATION

Note. Compare fault code to appropriate diagnostic chart.