Starting System — Acura MDX II (2006-2010)

Scheme 1

Scheme 1: Component Location Index

Symptom Troubleshooting Index

Symptom	Diagnostic procedure	Also check for
Engine does not start (does not crank)	Check for loose battery terminals or connections. Test the battery for a low charge (see BATTERY TEST ). Check the starter (see STARTER SYSTEM CIRCUIT TROUBLESHOOTING ). Check starter cut relay 1 and starter cut relay 2 (see POWER RELAY TEST ). Check the transmission range switch (see TRANSMISSION RANGE SWITCH TEST ). Check the ignition switch or wire (see TEST ).	Poor ground at G101
Engine cranks, but does not start	Check for PGM-FI DTCs. Check the fuel pressure (see FUEL PRESSURE TEST ). Check for a plugged or damaged fuel line (see FUEL LINE INSPECTION ). Check for a plugged fuel filter (see FUEL PRESSURE REGULATOR REPLACEMENT ). Check the throttle body (see THROTTLE BODY TEST ). Check for low engine compression (see ENGINE COMPRESSION INSPECTION ). Check for a damaged or broken timing belt.
Engine is hard to start	Check for PGM-FI DTCs. Check the fuel pressure (see FUEL PRESSURE TEST ). Check for a plugged or damaged fuel line (see FUEL LINE INSPECTION ). Check for a plugged fuel filter (see FUEL PRESSURE REGULATOR REPLACEMENT ).
Engine cranks slowly	Check for loose battery terminals or connections. Test the battery for a low charge (see BATTERY TEST ). Check the starter for binding (see STARTER OVERHAUL ). Check for excessive drag in the engine.
Multi-information display warning CHECK STARTING SYSTEM	Check for PGM-FI DTCs (see GENERAL TROUBLESHOOTING INFORMATION ).

TROUBLESHOOTING CHART

Scheme 2

Scheme 2: Circuit Diagram

Starter System Circuit Troubleshooting

Alternator, Regulator, Battery & Starter tester OTC3131 Available through the Acura Tool and Equipment Program 888-424-6857

Note. Air temperature must be between 59 and 100°F (15 and 38°C) during this procedure. After the inspection, you must reset the powertrain control module (PCM). Otherwise, the PCM will continue to stop the fuel injectors from functioning. The battery must be in good condition and fully charged.

Scheme 3

Scheme 3: Starter System Circuit Troubleshooting

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Connect the alternator, regulator, battery & starter tester (OTC3131) to the battery as shown. Ammeter, 0-400 A Voltmeter, 0-20 V (accurate within 0.1 volt) NOTE: The probe is not used for battery testing.
Do the BATTERY TEST. Does the display indicate GOOD or LOW CHARGE? YES - The battery is OK. Go to step 3. NO -If the tester indicates BAD BATTERY, replace the battery, then retest. If the tester indicates CHARGE & RETEST, charge the battery, then retest.
Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 on «HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM)»(/acura/mdx/ii-2006-2010/remont/testing-diagnostics/#fuel-and-emissions-systems__how-to-use-the-hds-honda) ).
Turn the ignition switch to ON (II).
Make sure the HDS communicates with the vehicle and the PCM. If it doesn't communicate troubleshoot the DLC circuit (see «DLC CIRCUIT TROUBLESHOOTING»(/acura/mdx/ii-2006-2010/remont/testing-diagnostics/#pgm-fi-system__dlc-circuit-troubleshooting) ).
Select PGM-FI, INSPECTION, then ALL INJECTORS OFF on the HDS.
Set the parking brake, then with the shift lever in the N or P position, turn the ignition switch to START (III). Does the starter crank the engine normally? YES - The starting system is OK. Go to step 15. NO - Go to step 8.
Turn the ignition switch to LOCK (0).
Check the electrical connections at the battery, the negative battery cable to the body, the engine ground cables, and the starter for looseness and corrosion. Then try cranking the engine again. Does the starter crank the engine normally? YES - Repairing the loose connection corrected the problem. The starting system is OK. Go to step 15 . NO - Based on the following symptoms, take the appropriate action: If the starter will not crank the engine at all, go to step 10. If the starter cranks the engine erratically or too slowly, go to step 12 . If the starter does not disengage from the torque converter ring gear when you release the key, replace the starter, or remove and disassemble it, and check for the following: Starter solenoid and switch malfunction Dirty drive gear or damaged overrunning clutch
Make sure the shift lever is in the N or P position, then disconnect the connector from the starter solenoid S terminal. Connect a jumper from the battery positive terminal to the solenoid S terminal. Does the starter crank the engine? YES - Go to step 11. NO - Remove the starter, and repair or replace it as necessary.
Check the following items in the order listed until you find the open circuit: NOTE: After the open circuit or high resistance in the circuit is found and repaired, go to step 15 . The WHT wire and connectors between the starter cut relay 1 and main under-hood fuse box. The BRN wire and connectors between the starter cut relay 2 and the starter cut relay 1. The WHT wire, BLK/WHT wire and connectors between the starter cut relay 2 and the starter. The ignition switch.(See «TEST»(/acura/mdx/ii-2006-2010/remont/ignition-switchsteering-lock/#ignition-switch__test) ). The transmission range switch and connector(See «TRANSMISSION RANGE SWITCH TEST»(/acura/mdx/ii-2006-2010/remont/automatic-trans/#automatic-transmission) ). The starter cut relay 1 and the starter cut relay 2. (see «POWER RELAY TEST»(/acura/mdx/ii-2006-2010/remont/body-electrical/#relays__power-relay-test) ). Are these items OK? YES - Go to step 12. NO - Repair or replace it, then go to step 12.
Connect alternator, regulator, battery & starter tester (OTC3131) to the battery.
Do the STARTING TEST. Does the display indicate cranking voltage greater than or equal to 8.0 V and is the current draw less than or equal to 375 A? YES - Go to step 14. NO - Replace the starter, or remove and disassemble it, and check for these problems Drag in the starter armature Short in the armature winding Excessive drag in the engine Open circuit in starter armature commutator segments Excessively worn starter brushes Open circuit in the starter brushes Dirty or damaged helical splines or drive gear Faulty over running clutch
Remove the starter, and inspect its drive gear and the torque converter ring gear for damage. Replace any damaged parts.
Select PCM reset (see «PCM RESET»(/acura/mdx/ii-2006-2010/remont/testing-diagnostics/#fuel-and-emissions-systems__pcm-reset) ) to cancel ALL INJECTORS OFF on the HDS.

Scheme 5

Scheme 5: Starter Solenoid Test

Do the battery terminal disconnection procedure(See «DISCONNECTION»(/acura/mdx/ii-2006-2010/remont/body-electrical/#battery__disconnection) .
Remove the battery and battery base (see step 11 on «ENGINE REMOVAL»(/acura/mdx/ii-2006-2010/remont/mechanical/#engine-removal-and-installation) ).
Disconnect the positive starter cable (A), S terminal connector (B), and motor cable (C).
Check the hold-in coil for continuity between the S terminal and the armature housing (ground) (D). There should be continuity. If there is continuity, go to step 6. If there is no continuity, replace the solenoid.
Check the pull-in coil for continuity between the S terminal and the M terminal. There should be continuity. If there is continuity, the solenoid is OK. If there is no continuity, replace the solenoid.
Reconnect the starter cable, S terminal connector, and motor cable.
Install the battery and battery base (See step 62 on «ENGINE INSTALLATION»(/acura/mdx/ii-2006-2010/remont/mechanical/#engine-removal-and-installation__engine-installation) .
Do the battery terminal reconnection procedure (See «RECONNECTION»(/acura/mdx/ii-2006-2010/remont/body-electrical/#battery__reconnection) .

Scheme 6

Scheme 6: Starter Performance Test

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Scheme 9

Disconnect the wire from the M terminal.
Make a connection for this test using the thickest (gauge) wire possible (preferably the same gauge as used on the vehicle). NOTE: To avoid damaging the starter, never leave the battery connected for more than 10 seconds.
Connect the battery as shown. Make sure you disconnect the starter motor wire from the solenoid. If the starter pinion moves out, it is working properly.
Disconnect the battery from the M terminal. If the pinion does not retract, the hold-in coil of the solenoid is working properly.
Disconnect the battery from the starter body. If the pinion retracts immediately, it is working properly.
Clamp the starter firmly in a vise.
Reconnect the wife to the M terminal.
Connect the starter to the battery as shown in the diagram, and confirm that the motor starts and keeps rotating.
If the electric current meets the specification when the battery voltage is at 11.5 V, the starter is working properly. Specification Electric Current: 90 A or less

Scheme 10

Scheme 10: Removal

Do the battery terminal disconnection procedure (See «DISCONNECTION»(/acura/mdx/ii-2006-2010/remont/body-electrical/#battery__disconnection) ).
Remove the air cleaner assembly (See «AIR CLEANER ELEMENT INSPECTION/ REPLACEMENT»(/acura/mdx/ii-2006-2010/remont/mechanical/#intake-air-system) ).
Remove the battery and battery base (See step 11 on «ENGINE REMOVAL»(/acura/mdx/ii-2006-2010/remont/mechanical/#engine-removal-and-installation) .
Remove the harness clamp (A).
Disconnect the positive starter cable (B) from the B terminal, then disconnect the connector (C) from the S terminal.
Remove the two bolts holding the starter.

Scheme 11

Scheme 11: Installation

Install the starter (A) using a new gasket (B), then install the harness clamp (C), and positive starter cable (D) and S terminal connector (E). Make sure the crimped side of the B terminal is facing out, away from the starter.
Install the battery base and battery (See step 62 on «ENGINE INSTALLATION»(/acura/mdx/ii-2006-2010/remont/mechanical/#engine-removal-and-installation__engine-installation) .
Install the air cleaner assembly (see «AIR CLEANER ELEMENT INSPECTION/ REPLACEMENT»(/acura/mdx/ii-2006-2010/remont/mechanical/#intake-air-system) ).
Do the battery terminal reconnection procedure (See «RECONNECTION»(/acura/mdx/ii-2006-2010/remont/body-electrical/#battery__reconnection) ).
Start the engine to make sure the starter works properly.

Scheme 12

Scheme 12: Disassembly/Reassembly

Scheme 13

Scheme 13: Brush Holder Removal

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Remove the starter (see «STARTER REMOVAL AND INSTALLATION»(/acura/mdx/ii-2006-2010/remont/starter/#starting-system) ).
Disconnect the wire from the M terminal, and remove the end cover.
Place a plastic pipe with an outside diameter of 29.4 mm (1.16 in.) on the armature.
Move the brush holder (A) up to the pipe (B) while holding the pipe so the brushes do not pop out from the holder. Armature Inspection and Test
Disassemble the starter as shown at the beginning of this procedure.
Inspect the armature for wear or damage from contact with the permanent magnet. If there is wear or damage, replace the armature.
Check the commutator (A) surface. If the surface is dirty or burnt, resurface it with an emery cloth or a lathe to the specifications in step 8, or recondition with #500 or #600 sandpaper (B).
Check the commutator diameter. If the diameter is below the service limit, replace the armature. Commutator Diameter Standard (New): 28.90-29.00 mm (1.138-1.142 in.) Service Limit: 28.00 mm (1.102 in.)
Measure the commutator (A) runout. If the commutator runout is within the service limit, check the commutator for carbon dust or brass chips between the segments. If the commutator runout is not within the service limit, replace the armature. Commutator Runout Standard (New): 0.02 mm (0.0008 in.) max. Service Limit: 0.05 mm (0.0002 in.)
Check the mica depth (A). If the mica is too high (B), undercut the mica with a hacksaw blade to the proper depth. Cut away all the mica (C) between the commutator segments. The undercut should not be too shallow, too narrow, or V-shaped (D). Commutator Mica Depth Standard (New): 0.50-0.90 mm (0.020-0.035 in.) Service Limit: 0.20 mm (0.008 in.)
Check for continuity between the segments of the commutator. If there is an open circuit between any segments, replace the armature.
Place the armature (A) on an armature tester (B). Hold a hacksaw blade (C) on the armature core. If the blade is attracted to the core or vibrates while the core is turned, the armature is shorted. Replace the armature.
Use an ohmmeter to check for continuity between the commutator (A) and the armature coil core (B), and between the commutator and the armature shaft (C). If there is continuity, replace the armature. Starter Brush Inspection
Measure the brush length. If it is shorter than the service limit, replace the brush holder assembly. Brush Length Standard (New): 15.0-16.0 mm (0.59-0.63 in.) Service Limit: 9.0 mm (0.35 in.) Starter Brush Holder Test
Check for continuity between the (+) brush (A) and (-) brush (B). If there is continuity, replace the brush holder assembly. Brush Spring Inspection
Insert the brush (A) into the brush holder, and bring the brush into contact with the commutator, then attach a spring scale (B) to the spring (C). Measure the spring tension at the moment the spring lifts off the brush. If it is not within the standard, replace the brush holder assembly. Spring Tension Standard (New): 22.3-27.3 N (2.27-2.78 kgf, 5.00-6.13 lbf) Planetary Gear Inspection
Check the planetary gears (A) and internal gear (B). Replace them if they are worn or damaged. Overrunning Clutch Inspection
Slide the overrunning clutch (A) along the shaft. Replace it, if it does not slide smoothly.
Hold the drive gear (B), and turn the overrunning clutch in the direction shown to make sure it turns freely. Also make sure the overrunning clutch locks in the opposite direction. If it does not lock, replace the overrunning clutch assembly.
If the starter drive gear is worn or damaged, replace the overrunning clutch assembly; the gear is not available separately. Check the condition of the torque converter ring gear. Replace it if the starter drive gear teeth are damaged. Starter Reassembly
When you replace the brush holder or the armature housing, you need to seat the new brushes. Slip a strip of #500 or #600 sandpaper, with the grit side up, between the commutator and each brush, and smoothly turn the armature. The contact surface of the brushes will be sanded to the same contour as the commutator.
Pry back each brush spring with a screwdriver, then position the brush on the brush holder about halfway out of its holder. Release the spring to hold it in place.
Push each brush down until it seats against the commutator, then release the spring against the end of the brush.
Install the armature housing (A) and armature (B) by aligning the slotted point (C) to the projection (D).
Install the armature into the housing.
Place the brush holder assembly on the armature, then move the brush holder (A) down to the armature.
Install the end cover to retain the brush holder.

Starting System Acura MDX II