Starting System: Diagnosis Mazda MX-5 NC

Pull-out Test

Note. Depending on the battery charge condition, the starter motor pinion may rotate while in an extended state. This is due to current flowing to the starter motor through the pull-in coil to turn the starter motor, and does not indicate an abnormality.

Scheme 2

1. Verify that the starter motor pinion is extended while battery positive voltage is connected to terminal S and the starter body is grounded. If the starter motor pinion is not extended, repair or replace the starter.

Scheme 3

1. Disconnect the motor wire from terminal M.
2. Connect battery positive voltage to terminal M and ground the starter body.
3. Pull out the drive pinion with a screwdriver. Verify that it returns to its original position when released. If it does not return, repair or replace the starter.

Scheme 4

1. Pull out the drive pinion with the battery positive voltage connected to terminal S and the starter body grounded. CAUTION: Applying power for more than 10 s can damage the starter. Do not apply power for more than 10s.
2. Measure the pinion gap while the drive pinion is extended. If not as specified, adjust with an adjustment washer (between drive housing front cover and magnetic switch). Starter pinion gap 0.5-2.0 mm {0.02-0.07 in}

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

1. Verify that there is no continuity between the commutator and the core at each segment using a tester. If there is continuity, replace the armature.
2. Verify that there is no continuity between the commutator and the shaft using a tester. If there is continuity, replace the armature.
3. Place the armature on V-blocks, and measure the runout using a dial indicator. Starter armature runout 0.1 mm {0.004 in} max.
4. Measure the commutator diameter. If not within the minimum specification, replace the armature. Starter commutator diameter Standard: 29.4 mm {1.16 in} Minimum: 28.8 mm {1.13 in}
5. Measure the segment groove depth of the commutator. If not within the minimum specification, undercut the grooves to the standard depth. Segment groove depth of starter commutator Standard: 0.5 mm {0.02 in} Minimum: 0.2 mm {0.008 in}

Scheme 10

Scheme 11

Scheme 12

1. Inspect for continuity between terminals S and M using a tester. If there is no continuity, replace the magnetic switch.
2. Inspect for continuity between terminal S and the body using a tester. If there is no continuity, replace the magnetic switch.
3. Verify that there is no continuity between terminals M and B using a tester. If there is continuity, replace the magnetic switch.

Scheme 13

1. Verify that there is no continuity between each insulated brush and plate using a tester. If there is continuity, replace the brush holder.
2. Measure the brush length. If any brush is worn almost to or beyond the minimum specification, replace all of the brushes.
3. Measure the brush spring force using a spring balance. If not within the minimum specification, replace the brush and brush holder component. Starter brush spring force Standard: 15.0-20.4 N {1.53-2.08 kgf, 3.38-4.58 lbf} Minimum: 2.75 N {0.28 kgf, 0.62 lbf}

Scheme 14

1. Disassemble in the order indicated in (Scheme 16).
2. Assemble in the reverse order of disassembly.

STARTER INTERLOCK SWITCH INSPECTION [MT]

Scheme 15

Scheme 16

1. Remove the battery cover.
2. Disconnect the negative battery cable. (See «BATTERY REMOVAL/INSTALLATION [LF]»(ref-244448-S25513985422006092400000).)
3. Disconnect the starter interlock switch connector.
4. Verify that the continuity is as indicated in see scheme 20 using a tester. If the continuity is not as indicated in see scheme 20, replace the starter interlock switch.