Troubleshooting

Using Troubleshooting Chart

If you are experiencing a problem that is not listed in this chart, see your authorized dealer for service.

When you have checked all the possible causes listed and you are still experiencing the problem, see your authorized dealer.

Engine


If	Check
Engine Will Not Crank	Forward/reverse pedals out of neutral position. Mow/Transport lever not in transport position. Park brake not engaged. Backlapping valve engaged. Loose or corroded battery connections. Low battery output. Sulfated or worn out battery. Starter faulty. Blown fuse. Melted fusible link.
Engine Hard To Start	Gas Model: Faulty spark plug. Loose or corroded electrical connections. Stale fuel. Plugged filter. Diesel Model: Air in system.
Engine Will Not Start	Diesel Model: Fuel shut-off valve closed. No fuel. Wrong fuel. Plugged fuel filter. Stale fuel. Gas Model: Spark plug wires loose or disconnected.
Engine Misses Under Load	Gas Model: Faulty spark plug. Stale fuel. Diesel Model: Air in system.
Engine Runs Rough When Hot	Fuel tank vent plugged. Dirty fuel filter. Gas Model: Engine or carburetor not grounded well. Gas Model: Debris in carburetor. Gas Model: Coolant low in radiator. Gas Model: Dirt and debris in radiator fins.
Engine Runs Unevenly	Loose electrical connections. Choke or throttle cable sticking. Diesel Model: Air in system.
Engine Will Not Idle	Spark plug not gapped correctly. Faulty spark plug. Loose throttle cable. Improper idle speed adjustment.
Engine Backfires	Gas Model: Faulty spark plug. Allow engine to cool prior to shutdown.
Engine Knocks	Stale or low octane fuel. Engine overloaded. Low engine speed.
Engine Loses Power	Engine overheating. Too much oil in engine. Dirty air cleaner. High altitude operation. Gas Model: Faulty spark plug.
Engine Overheats	Plugged oil cooler. Air intake grille screen plugged. Low coolant level. Engine oil low.
Low Oil Pressure	Engine oil level low. Plugged oil filter. Faulty oil pump. (See your John Deere dealer)

Electrical


If	Check
Starter Does Not Work	Loose or corroded connections. Low battery output. Sulfated or worn out battery. Faulty starter.
Starter Cranks Slowly	Low battery output. Sulfated or worn out battery. Engine oil too heavy. Loose or corroded connections.
Entire Electrical System Does Not Work	Blown fuse. Loose or corroded connections. Sulfated or worn out battery.
Dead Battery	Shorted starter solenoid. Key switch not turned to "STOP" position. Sulfated or worn out battery.
Battery Light Goes On When Engine Is Running	Low engine speed. Faulty voltage regulator. Faulty battery. Faulty alternator. Grounded wire in circuit.
Indicator Lights Do Not Come On In "Start" Position	Faulty bulb. Faulty wiring. Faulty sensor.
Battery Will Not Take A Charge	Dead cell in battery. Loose or corroded connections. Sulfated or worn out battery. Fluid level low.

Electric Mower Drive System - 2500E

c CAUTION: Avoid injury! Blades are sharp and rotate quickly:

· Keeps hands and feet away from cutting reels while machine is running.

· Always wear gloves while working on cutting reels.

· Watch for rotation of cutting reels. Rotating one cutting reel can cause another blade or cutting reel to rotate.

If a reel does not turn and no code exists, shut down machine and remove debris.

If more than one motor is stopped, an erroneous code can be seen at the reel controller diagnostic light.

Raise cutting units, shut machine down and clear any debris or restriction than can prevent reels from turning. If erroneous code is still present or more than one cutting unit does not operate after restart, contact your John Deere dealer.


If	Check
Slow Reel Speed - All Cutting Units	Adjust reel speed control. Reels too tight against bed knife. Corrosion in connecter between potentiometer and harness. Corrosion between harness and right side motor controller. Failed or disconnected speed control.
Slow Reel Speed - One or Two Cutting Units	Open speed control circuit between control box and reel motor control module(s).
Left and Right Reels Rotating in Wrong Direction	Left and right reel motor cables connected to wrong connectors.
Right Reel Rotating in Wrong Direction	Forward/reverse switch connector disconnected. Forward/reverse switch failed in forward position. Poor connection between switch and control harness. Poor connection between control harness and right side controller.
Left and Center Reels Rotating in Wrong Direction During Backlap	Forward/reverse switch connector disconnected. Forward/reverse switch failed in reverse position.
Reel Motors Fail to Operate	Mow solenoid connector disconnected. Mow-transport switch connector disconnected. Mow-transport switch failed. Power cable terminals loose or corroded. Ground cable terminals loose or corroded. 48 volt alternator failed.
Reel Motor Fails to Operate	Motor cable connectors loose or not connected. Motor failed. Motor controller failed. Power cable terminals loose or corroded. Ground cable terminals loose or corroded.
Codes Appear Erratically	Adjust Mow-transport linkage - should have 1-3 mm between linkage and switch.
Reel Controller Diagnostic Light Flashes Once	Motor malfunction - motor failed to start. Large motor connector disconnected. Cutting reel jammed by debris. Poor connection or bent pin in 6 pin connector between motor and controller.
Reel Controller Diagnostic Light Flashes Two Times	Motor stopped during normal operation. Cutting reel jammed by debris. Poor connection or bent pin in 6 pin connector between motor and controller.
Reel Controller Diagnostic Light Flashes Three Times	Motor malfunction. Poor connection in motor to controller 6 pin connector
Reel Controller Diagnostic Light Flashes Four Times	48 volt alternator output voltage is over 68 volts. 48 volt alternator malfunction. Loose or corroded terminals.
Reel Controller Diagnostic Light Flashes Five Times	48 volt alternator output voltage is below 28 volts. Loose or corroded terminals. 48 volt alternator malfunction. Idle speed of engine too low to produce 48 volts.
Reel Controller Diagnostic Light Flashes Six Times	Loose or bad connection to motor speed control. Right motor controller malfunction. Potentiometer voltage low. Loose or bad connection between right controller and logic wiring harness.
Reel Controller Diagnostic Light Flashes Seven Times	Shorted wiring to motor speed control. Right motor controller malfunction. Failed speed control potentiometer.
Reel Controller Diagnostic Light Flashes Eight Times	Poor connection at small motor connector. Motor failed. Controller failed. No current flow in motor. Poor connection in large 3 pin connector.
Reel Controller Diagnostic Light Flashes Nine Times	Shorted wiring. Motor controller malfunction.
Reel Controller Diagnostic Light Flashes Ten Times	Motor overheated. Large motor connector corroded and small motor connector disconnected or corroded.
Reel Controller Diagnostic Light Flashes Eleven Times	Small motor connector loose or disconnected. Motor trying to start under heavy load. Moisture in small connector. Motor failed. Controller failed.
Reel Controller Diagnostic Light Flashes Twelve Times	Motor failed. Moisture in large connector. Shorted large wires between motor and controller.
Reel Controller Diagnostic Light Flashes Thirteen Times	Motor failed from internal short. Shorted large wires to frame.

Hydraulic Mower Drive System - 2500A


If	Check
Slow Reel Speed	Oil level low. (See Checking Hydraulic Oil Level in SERVICE TRANSMISSION section). Oil overheats. Wrong oil. Adjust reel speed on backlapping valve. Reels too tight against bed knife. Backlapping valve inlet screen clogged. Dirty relief valve. Worn or stuck relief valve. Worn pump or motor(s).
Oil Overheats	Low oil level. High ambient temperatures working under heavy loads. Dull cutting reels. Cutting reels adjusted with interference. Park brake locked. Wrong oil. Dirty oil. High-pressure internal leak.
Foaming Oil	Trapped air after repairs. Low oil level. Wrong oil. Water in oil. Air leaks.
Noisy Pump	Low oil level. Air leaks on suction side.
Hydraulic System Fails to Function	Wrong oil. Low oil level. Clogged suction line. Air leaks. Faulty relief valve. Faulty pump or motor(s).

Hydrostatic Drive


If	Check
Machine Will Not Move Forward Or Backward	Low oil level. Wrong Oil. Control linkage out of adjustment. Park brake not disengaged. Forward/reverse cable broken. Low charge pressure. Internal pump damage.
Noisy System	Low oil level. Air in system. Oil filter plugged. Internal pump or motor damage. Park brake locked. Cutting reels adjusted improperly.
Accelerates Slowly	Low oil level. Control linkage loose or out of adjustment. Air in system. Low charge pressure. Park brake locked.
Machine Moves With Engine Running And Hydrostatic Control Pedals In Neutral	Creep linkage out of adjustment.
Pedals Do Not Return To Neutral	Spring out of adjustment.

Cutting Units


If	Check
Poor Cut: Jagged Cut Quality or Browning	Bed knife to reel out of adjustment. Reel dull. Bed knife dull.
Poor Cut: Marcelling or Hop	Ground speed too high or engine rpm too slow (not at rated 3350 50 rpm).
Poor Cut: Streaked Appearance	Bed knife and/or reel grooved, ribbed, or rifled due to reel-to-bed knife adjustment too tight or running machine without grass in the reels. Backlap valve reel speed adjustment too slow
Grass Buildup On Rolls	Scraper out of adjustment.
Mowers Will Not Raise/lower	Failed hand switch. Broken or shorted wiring. Not enough oil in reservoir. Defective solenoid. Control valve spool does not move. Pump does not rotate. No output from pump.
Reels Will Not Rotate	Reels too tight against bed knife. Mow/transport lever not engaged. Mow/transport lever not engaged. Cutting reels plugged. Not enough oil in reservoir. Hydraulic pump not rotating. Broken or shorted wiring. Defective solenoid. Control valve spool does not move. No output from pump.
Mower Reels Squeal	Operating reel without grass (Grass clippings lubricate cutting reel and bed knife). Improper bed knife to reel adjustment.
Cutting Reels Operating In Reverse	Backlapping valve engaged. Cutting reel motor hoses reversed.
Oil Leaks From Cutting Unit Motor	Motor seal leaks. Loose fittings.