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Home >> Mazda >> 2007 >> B3000 Base, Automatic >> Repair and Diagnosis >> Body & Frame >> Ignition Switch/Steering Lock >> Troubleshooting (Power Systems) >> Pinpoint Test 3: DTC B1555 - Ignition Run Circuit Failure Or No Power In Run >> Possible Causes
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Possible Causes

CAUTION:
  • Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.
DTC B1555 - IGNITION RUN CIRCUIT FAILURE OR NO POWER IN RUN - PINPOINT TEST REFERENCE

PINPOINT TEST 3 DTC B1555 - IGNITION RUN CIRCUIT FAILURE OR NO POWER IN RUN
STEP INSPECTION ACTION
1 CHECK THE VOLTAGE SUPPLY TO THE IGNITION SWITCH
  • Key in OFF position.
  • Disconnect: Ignition switch C-250.
  • Measure the voltage between ground and:
    • ignition switch C-250 pin 2, circuit (R), harness side.
    • ignition switch C-250 pin 7, circuit (R), harness side.
    • ignition switch C-250 pin 9, circuit (R), harness side.
  • Are the voltages greater than 10 volts? 
 Yes Go to next step.
No Verify battery junction box (BJB) fuse 9 (40A) is OK. If OK, repair circuit (Y) for an open. Clear the DTCs. Test the system for normal operation.
2 CHECK THE IGNITION SWITCH
  • Carry out the ignition switch component test. See the component test at the end of the test.
  • Is the ignition switch OK ? 
 Yes Go to next step.
No Install a new ignition switch. See IGNITION SWITCH , . Clear the DTCs. Test the system for normal operation.
3 CHECK THE VOLTAGE SUPPLY TO THE SMART JUNCTION BOX (SJB)
  • Disconnect: Smart Junction Box SJB J-2280b.
  • Disconnect: SJB J-2280c.
  • Connect: Ignition switch C-250.
  • Measure the voltage between ground and:
    • SJB C2280b pin 17, circuit (BRA'), harness side.
    • SJB C2280b pin 29, circuit (W/O), harness side.
    • SJB C2280C pin 32, circuit (V/G), harness side.
  • Are the voltages greater than 10 volts? 
 Yes Go to next step.
No Repair the affected circuit(s). Clear the DTCs. Test the system for normal operation.
4 CHECK FOR CORRECT SJB OPERATION
  • Disconnect all the SJB connectors.
  • Check for:
    • corrosion.
    • pushed-out pins.
    • spread terminals.
  • Connect all the SJB connectors and make sure they seat correctly.

    Operate the system and verify the concern is still present.

  • Is the concern still present? 
 Yes Install a new SJB. See SMART JUNCTION BOX (SJB) , . Test the system for normal operation.
No The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. Clear the DTCs. Test the system for normal operation.


CAUTION:
  • Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multimeter probes.
NO POWER IN START - PINPOINT TEST REFERENCE

PINPOINT TEST 4 NO POWER IN START
STEP INSPECTION ACTION
1 CHECK THE STARTER OPERATION
  • Key in START position.
  • Does the starter motor engage? 
 Yes Go to next step.
No Install a new ignition switch. See IGNITION SWITCH , . Test the system for normal operation.
2 CHECK THE VOLTAGE TO THE IGNITION SWITCH
  • Key in OFF position.
  • Disconnect: Ignition switch C-250
  • Measure the voltage between ground and:
    • ignition switch C-250 pin 2, circuit (R), harness side.
    • ignition switch C-250 pin 9, circuit (R), harness side.
  • Are the voltages greater than 10 volts? 
 Yes Go to next step.
No Verify battery junction box (BJB) fuse 9 (40A) is OK. If OK, repair the affected circuit(s). Test the system for normal operation.
3 CHECK THE IGNITION SWITCH
  • Carry out the ignition switch component test. See the component test at the end of the test.
  • Is the ignition switch OK ? 
 Yes Repair circuit (L/W) or circuit (W/O) for an open. Test the system for normal operation.
No Install a new ignition switch. See IGNITION SWITCH , . Test the system for normal operation.

Ignition Switch Component Test 

IGNITION SWITCH COMPONENT TEST

Circuit to test Connect self-powered test light or ohmmeter Move key to these positions A good switch will indicate
Run power circuit  3 and 7
8 and 9
12 and 13		 Off/lock Open circuit
Run power circuit  3 and 7
8 and 9
12 and 13		 Accessory Open circuit
Run power circuit  3 and 7
8 and 9
12 and 13		 Run Closed circuit
Run power circuit  3 and 7
8 and 9
12 and 13		 Start Open circuit
Run/Start power circuit  1 and 2 Off/Lock Open circuit
Run/Start power circuit  1 and 2 Accessory Open circuit
Run/Start power circuit  1 and 2 Run Closed circuit
Run/Start power circuit  1 and 2 Start Closed circuit
Ace power circuit  2 and 3 Off/Lock Open circuit
Ace power circuit  2 and 3 Accessory Closed circuit
Ace power circuit  2 and 3 Run Open circuit
Ace power circuit  2 and 3 Start Open circuit
Start power circuit  5 and 9 Off/Lock Open circuit
Start power circuit  5 and 9 Accessory Open circuit
Start power circuit  5 and 9 Run Open circuit
Start power circuit  5 and 9 Start Closed circuit


IGNITION KEY IS HARD TO TURN - PINPOINT TEST REFERENCE

PINPOINT TEST 5 THE IGNITION KEY IS HARD TO TURN
STEP INSPECTION ACTION
1 CHECK THE STEERING WHEEL POSITION
NOTE:
  • The ignition lock cylinder should return from the START position back to the ON position without assistance.
  • Check to see if the steering wheel is turned and locked full left or full right.
  • Is the steering wheel locked full left or full right? 
 Yes Apply turning effort to the steering wheel in the direction of lock while turning the key to the ON position. Test the system for normal operation.
No Go to next step.
2 CHECK THE IGNITION LOCK CYLINDER KEY
  • Check the ignition lock cylinder key for burrs, damaged key or incorrect key cut.
  • Is the key OK? 
 Yes Go to next step.
No Replace the ignition key. Test the system for normal operation.
3 CHECK THE IGNITION LOCK CYLINDER
  • Remove the ignition lock cylinder. See IGNITION LOCK CYLINDER - FUNCTIONAL , .
  • Check the ignition lock cylinder by rotating the ignition lock cylinder through all of the switch positions.
  • Does the ignition lock cylinder stick or bind in any of the positions? 
 Yes Install a new ignition lock cylinder. See IGNITION LOCK CYLINDER - FUNCTIONAL , .
No Go to next step.
4 CHECK THE IGNITION LOCK CYLINDER HOUSING
CAUTION:
  • Do not apply lubricant to the inside of the ignition switch.
  • Check for a binding or sticking ignition switch in the steering column lock module or insufficient lube.
  • Is the steering column lock module and lubrication OK? 
 Yes Install a new ignition switch. See IGNITION SWITCH , . Test the system for normal operation.
No Repair or lubricate as necessary. Test the system for normal operation.
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