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Symptom Troubleshooting Index

SYMPTOM TROUBLESHOOTING INDEX

Symptom Probable cause(s) Notes
When you turn the ignition switch ON (II), the D5 indicator comes on and stays on in all shift lever positions, or it never comes on at all A problem in the D5 indicator circuit Check the D5 indicator circuit (see D5 INDICATOR CIRCUIT TROUBLESHOOTING  ).
Shift lever cannot be moved from P while you are pressing on the brake pedal A problem in the shift lock system of the interlock system Check the interlock system - shift lock system circuit (see SHIFT LOCK SYSTEM CIRCUIT TROUBLESHOOTING  ).
Ignition switch cannot be moved from ACC (I) to LOCK (0) (key is pushed in, shift lever in P) A problem in the key interlock system of the interlock system Check the interlock system - key interlock system circuit (see KEY INTERLOCK SYSTEM CIRCUIT TROUBLESHOOTING  ).
Shift lever cannot pass through R from N A problem in the reverse lock system of the interlock system Check the interlock system - reverse lock system circuit (see REVERSE LOCK SYSTEM CIRCUIT TROUBLESHOOTING  ).
When you turn the ignition switch ON (II), the A/T TEMP indicator comes on and stays on or never comes on at all A problem in the A/T TEMP indicator circuit Check the A/T TEMP indicator circuit (see A/T TEMP INDICATOR CIRCUIT TROUBLESHOOTING  ).
SYMPTOM TROUBLESHOOTING INDEX

Symptom Probable cause(s) Notes
Engine runs, but vehicle does not move in any gear
  1. Low ATF level
  2. Shift cable broken or out of adjustment
  3. Connection between shift cable and transmission or body is worn
  4. ATF pump worn or binding
  5. Regulator valve stuck or spring worn
  6. ATF strainer clogged
  7. Mainshaft worn or damaged
  8. Final gears worn or damaged
  9. Park mechanism defective
  10. Transmission-to-engine assembly error
  11. Axle disengaged
  • Check the ATF level and check the ATF cooler lines for leakage and loose connections. If necessary, clean the ATF cooler lines.
  • Check for a loose shift cable at the shift lever and the transmission control lever.
  • Improper alignment of ATF pump and torque converter housing may cause ATF pump seizure. The symptoms are mostly an rpm-related ticking noise or a high pitched squeak.
  • Check the line pressure.
  • Check the ATF strainer for debris. If the strainer is clogged, find the damaged components that caused the debris.
  • Inspect the differential pinion gears for wear. If the differential pinion gears are worn, replace the differential assembly, replace the ATF strainer, and thoroughly clean the transmission, and clean the cooler and lines. Replace the torque converter.
  • Be careful not to damage the torque converter housing when replacing the main ball bearing. You may also damage the ATF pump when you torque down the main valve body. This will result in ATF pump seizure if not detected. Use the proper tools.
  • Install the main seal flush with the torque converter housing. If you push it into the torque converter housing until it tops out, it will block the fluid return passage and result in damage.
Vehicle moves in R, but not in D5, D4, D3, 2, or 1
  1. 1st accumulator defective
  2. Idler gears worn or damaged
  3. 1st clutch defective
  • Check the 1st clutch pressure.
  • Inspect the secondary shaft and 1st/1st-hold clutch assembly for wear and damage.
  • Inspect the clutch piston and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Vehicle moves in 2 and R, but not in D5, D4, D3, or 1
  1. 1st gear one-way clutch defective
  2. 1st gears worn or damaged
  3. 1st clutch defective
  • Check the 1st clutch pressure.
  • Inspect the secondary shaft and 1st/1st-hold clutch assembly for wear and damage.
  • Inspect the clutch piston and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Vehicle moves in D5, D4, D3, 2, and R, but not in 1
  1. 1st-hold accumulator defective
  2. 1st-hold clutch defective
  • Check the 1st-hold clutch pressure.
  • Inspect the secondary shaft and 1st/1st-hold clutch assembly for wear and damage.
  • Inspect the clutch piston and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Vehicle moves in D5, D4, D3, 1, and R, but not in 2
  1. 2nd accumulator defective
  2. 2nd clutch defective
  • Check the 2nd clutch pressure.
  • Inspect the secondary shaft and 2nd clutch assembly for wear and damage.
  • Inspect the clutch piston and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Vehicle moves in D5, D4, D3, 2, and 1, but not in R (or moves forward in R)
  1. Shift fork shaft stuck
  2. Modulator valve defective
  3. Reverse CPC valve defective
  4. 5th accumulator defective
  5. 5th clutch defective
  6. Reverse gears worn or damaged
  • Check the line pressure and 5th clutch pressure.
  • Check for a missing shift fork bolt on the shift fork shaft.
  • Check the ATF strainer for debris. If the ATF strainer is clogged with particles of steel or aluminum, inspect the ATF pump. If the ATF pump is OK, find the damaged components that caused the debris. If no cause for the contamination is found, replace the torque converter.
  • Inspect the reverse selector gear teeth chambers, and inspect the engagement teeth chambers of the countershaft 5th gear and reverse gear. Replace the reverse gears and the reverse selector if they are worn or damaged. If the transmission makes clicking, grinding, or whirring noises, also replace the mainshaft 5th gear, reverse idler gear, and countershaft 5th gear.
  • Inspect the clutch piston, clutch piston check valve, and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clearance with the clutch end plate.
Poor acceleration; flares when starting off in D5, D4, D3, and R
  1. Low ATF level
  2. Shift cable broken or out of adjustment
  3. ATF pump worn or binding
  4. Regulator valve stuck or spring worn
  5. ATF strainer clogged
  6. Torque converter check valve defective
  • Check the ATF level and check the ATF cooler lines for leakage and loose connections. If necessary, clean the ATF cooler lines.
  • Check for a loose shift cable at the shift lever and the transmission control lever.
  • Check the line pressure.
  • Check the ATF strainer for debris. If the strainer is clogged, find the damaged components that caused the debris.
  • Improper alignment of ATF pump and torque converter housing may cause ATF pump seizure. The symptom is mostly an rpm-ticking noise or a high pitched squeak.
  • Be careful not to damage the torque converter housing when replacing the main ball bearing. You may also damage the ATF pump when you torque down the main valve body. This will result in ATF pump seizure if not detected. Use the proper tools.
Poor acceleration; flares when starting off in D5, D4, D3, and R; stall speed high in D5, D4, D3, 2, and 1
  1. 1st accumulator defective
  2. 1st clutch defective
  • Check the 1st clutch pressure.
  • Inspect the clutch piston and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Poor acceleration; flares when starting off in D5, D4, D3, and R; stall speed high in 2
  1. 2nd accumulator defective
  2. 2nd clutch defective
  • Check the 2nd clutch pressure.
  • Inspect the clutch piston and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Poor acceleration; flares when starting off in D5, D4, D3, and R; stall speed high in R
  1. Shift solenoid valve C defective
  2. Shift cable broken or out of adjustment
  3. Reverse CPC valve defective
  4. 5th accumulator defective
  5. 5th clutch defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the O-ring, and check the shift solenoid valve seizure.
  • Check for a loose shift cable at the shift lever and the transmission control lever.
  • Check the 5th clutch pressure.
  • Inspect the clutch piston and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Poor acceleration; flares when starting off in D5, D4, D3, and R; stall speed low
  1. Torque converter clutch solenoid valve defective
  2. Torque converter one-way clutch defective
  3. Engine output low
  4. Torque converter clutch piston defective
  5. Lock up shift valve defective
 Check for a stuck lock up valve in the valve body.
Engine idle vibration
  1. Low ATF level
  2. Torque converter clutch solenoid valve defective
  3. Drive plate defective or transmission misassembled
  4. Engine output low
  5. Torque converter clutch piston defective
  6. ATF pump worn or binding
  7. Lock up shift valve defective
  • Set the idle RPM in gear to the specified idle speed. If it is still no good, adjust the engine and transmission mounts.
  • Check the ATF level and check the ATF cooler lines for leakage and loose connections. If necessary, clean the ATF cooler lines.
Vehicle moves in N
  1. Excessive ATF
  2. Foreign material in separator plate orifice
  3. Relief valve defective
  4. Lubrication control valve defective
  5. 1st-hold clutch defective
  6. 1st clutch defective
  7. 2nd clutch defective
  8. 3rd clutch defective
  9. 4th clutch defective
  10. 5th clutch defective
  11. Clutch end plate clearance incorrect
  12. Needle bearing seized up, worn, or damaged
  13. Thrust washer seized up, worn, or damaged
  • Check the ATF level, and drain the ATF if necessary.
  • Check all clutch pressures.
  • Inspect the clutch piston, clutch piston check valve, and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Late shift after shifting from N to D5, D4, and D3, or excessive shock when shifting
  1. Shift solenoid valve C defective
  2. A/T clutch pressure control solenoid valve A defective
  3. A/T clutch pressure control solenoid valve B defective
  4. A/T clutch pressure control solenoid valve C defective
  5. Shift cable broken or out of adjustment
  6. Connection between shift cable and transmission or body is worn
  7. Input shaft (mainshaft) speed sensor defective
  8. Output shaft (countershaft) speed sensor defective
  9. ATF temperature sensor defective
  10. CPC valve A defective
  11. CPC valve B defective
  12. CPC valve C stuck
  13. Foreign material in separator plate orifice
  14. Shift valve C defective
  15. Shift valve E defective
  16. Servo control valve defective
  17. 1st accumulator defective
  18. 1st check ball stuck
  19. One-way check ball stuck
  20. 1st clutch defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the O-ring, and check the shift solenoid valve for seizure.
  • Inspect the A/T clutch pressure control solenoid valve body gasket and ATF feed pipes for wear and damage. If the A/T clutch pressure control solenoid valve is stuck, inspect the CPC valves.
  • Check for a loose shift cable at the shift lever and the transmission control lever.
  • Check the 1st clutch pressure.
  • Inspect the clutch piston, clutch piston check valve, and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Late shift after shifting from N to R, or excessive shock when shifting
  1. Shift solenoid valve C defective
  2. A/T clutch pressure control solenoid valve B defective
  3. A/T clutch pressure control solenoid valve C defective
  4. Shift cable broken or out of adjustment
  5. Connection between shift cable and transmission or body is worn
  6. Input shaft (mainshaft) speed sensor defective
  7. Output shaft (countershaft) speed sensor defective
  8. ATF temperature sensor defective
  9. Shift fork shaft stuck
  10. CPC valve C stuck
  11. Reverse CPC valve defective
  12. Foreign material in separator plate orifice
  13. Shift valve E defective
  14. 5th accumulator defective
  15. 5th clutch defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the O-ring, and check the shift solenoid valve for seizure.
  • Inspect the A/T clutch pressure control solenoid valve body gasket and ATF feed pipes for wear and damage. If the A/T clutch pressure control solenoid valve is stuck, inspect the CPC valves.
  • Check for a loose shift cable at the shift lever and the transmission control lever.
  • Check the 5th clutch pressure.
  • Inspect the clutch piston, clutch piston check valve, and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
The A/T does not shift
  1. Input shaft (mainshaft) speed sensor defective
  2. Output shaft (countershaft) speed sensor defective
  3. Modulator valve defective
  • Check the D5 indicator, and check for loose connectors.
  • Check the line pressure.
Erratic shifting: fails to shift in D5, D4, and D3; starts off in 5th
  1. Shift solenoid valve B defective
  2. Shift valve B defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the O-ring, and check the shift solenoid valve for seizure.
Erratic shifting: fails to shift in 2; starts off in 4th
  1. Shift solenoid valve B defective
  2. Shift valve B defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the O-ring, and check the shift solenoid valve for seizure.
Erratic shifting: fails to shift in D5, D4, D3, and 1; starts off in 3rd
  1. Shift solenoid valve A defective
  2. Shift valve A defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the O-ring, and check the shift solenoid valve for seizure.
Erratic shifting: fails to shift in 2; starts off in 1st
  1. Shift solenoid valve A defective
  2. Shift valve A defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the O-ring, and check the shift solenoid valve for seizure.
Excessive shock or flares on all upshifts and downshifts
  1. A/T clutch pressure control solenoid valve A defective
  2. Input shaft (mainshaft) speed sensor defective
  3. Output shaft (countershaft) speed sensor defective
  4. ATF temperature sensor defective
  5. CPC valve A defective
  6. Foreign material in separator plate orifice
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the A/T clutch pressure control solenoid valve body gasket and ATF feed pipes for wear and damage. If the A/T clutch pressure control solenoid valve is stuck, inspect the CPC valves.
  • Inspect the sensor O-rings.
Excessive shock or flares on 1-2 upshift or 2-1 downshift
  1. Foreign material in separator plate orifice
  2. 2nd accumulator defective
  3. 2nd check ball stuck
  4. 2nd clutch defective
  • Check the 1st and 2nd clutch pressures.
  • Inspect the clutch piston, clutch check valve, and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Excessive shock or flares on 2-3 upshift or 3-2 downshift
  1. Shift solenoid valve C defective
  2. A/T clutch pressure control solenoid valve B defective
  3. 3rd clutch transmission fluid pressure switch defective
  4. CPC valve B defective
  5. Foreign material in separator plate orifice
  6. Shift valve C defective
  7. 2nd accumulator defective
  8. 3rd accumulator defective
  9. 2nd check ball stuck
  10. 2nd clutch defective
  11. 3rd clutch defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the O-rings, and check the shift solenoid valve for seizure.
  • Check for clogged orifice in the transmission fluid pressure switch connector. If the orifice is clogged, remove it and clean the connector.
  • Check the 2nd and 3rd clutch pressures.
  • Inspect the clutch piston, clutch check valve and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Excessive shock or flares on 3-4 upshift or 4-3 downshift
  1. Shift solenoid valve C defective
  2. A/T clutch pressure control solenoid valve B defective
  3. 4th clutch transmission fluid pressure switch defective
  4. CPC valve B defective
  5. Foreign material in separator plate orifice
  6. Shift valve C defective
  7. 3rd accumulator defective
  8. 4th accumulator defective
  9. 3rd clutch defective
  10. 4th clutch defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the O-rings, and check the shift solenoid valve for seizure.
  • Check for clogged orifice in the transmission fluid pressure switch connector. If the orifice is clogged, remove it and clean the connector.
  • Check the 3rd and 4th clutch pressures.
  • Inspect the clutch piston, clutch check valve and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Excessive shock or flares on 4-5 upshift or 5-4 downshift
  1. Shift solenoid valve C defective
  2. A/T clutch pressure control solenoid valve B defective
  3. A/T clutch pressure control solenoid valve C defective
  4. CPC valve B defective
  5. CPC valve C defective
  6. Foreign material in separator plate orifice
  7. Shift valve C defective
  8. Shift valve E defective
  9. Kick down valve or kick down short valve defective
  10. 4th accumulator defective
  11. 5th accumulator defective
  12. 4th clutch defective
  13. 5th clutch defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the O-rings, and check the shift solenoid valve for seizure.
  • Check the 4th and 5th clutch pressures.
  • Inspect the clutch piston, clutch check valve and O-rings. Check the spring retainer for wear and damage. Inspect the clutch end-plate-to-top-disc clearance. If the clearance is out of tolerance, inspect the clutch discs and plates for wear and damage. If the discs and plates are worn or damaged, replace them as a set. If they are OK, adjust the clutch end plate clearance.
Noise from transmission in all shift lever positions
  1. ATF pump worn or binding
  2. Idler gears worn or damaged
  3. Thrust washer seized up, worn, or damaged
 Improper alignment of ATF pump and torque converter housing may cause ATF pump seizure. The symptoms are mostly an rpm-related ticking noise or a high pitched squeak.
Vehicle does not accelerate above 31 mph (50 km/h) Torque converter one-way clutch defective Replace torque converter.
Vibration in all shift lever positions Drive plate defective or transmission misassembled
  • Set the idle RPM in gear to the specified idle speed. If still no good, adjust the engine and transmission mounts.
  • Check the stall speed.
Shift lever does not operate smoothly
  1. Transmission range switch defective or out of adjustment
  2. Shift cable broken or out of adjustment
  3. Connection between shift cable and transmission or body is worn
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the transmission range switch. If the transmission range switch is faulty, replace it. If the transmission range switch is out of adjustment, adjust it and the shift cable.
  • Check for a loose shift cable at the shift lever and the transmission control lever.
Transmission does not shift into P
  1. Shift cable broken or out of adjustment
  2. Connection between shift cable and transmission or body is worn
  3. Park mechanism defective
  • Check for a loose shift cable at the shift lever and the transmission control lever.
  • Check the park pawl, control shaft, and park lever link for wear and damage. Check if the control shaft lever pin is disengage from the manual valve guide.
Torque converter clutch does not disengage
  1. Torque converter clutch solenoid valve defective
  2. A/T clutch pressure control solenoid valve C defective
  3. Torque converter clutch piston defective
  4. Lock up shift valve defective
  5. Lock up control valve defective
  6. Lock up timing valve defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the A/T clutch pressure control solenoid valve C body gasket for wear and damage. If the A/T clutch pressure control solenoid valve C is stuck, inspect the CPC valves.
Torque converter clutch does not operate smoothly
  1. Torque converter clutch solenoid valve defective
  2. A/T clutch pressure control solenoid valve C defective
  3. Lock up clutch piston defective
  4. Torque converter check valve defective
  5. Lock up shift valve defective
  6. Lock up control valve defective
  7. Lock up timing valve defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the A/T clutch pressure control solenoid valve C body gasket for wear and damage. If the A/T clutch pressure control solenoid valve C is stuck, inspect the CPC valves.
  • Center all engine mounts.
Torque converter clutch does not engage
  1. Torque converter clutch solenoid valve defective
  2. A/T clutch pressure control solenoid valve C defective
  3. Input shaft (mainshaft) speed sensor defective
  4. Output shaft (countershaft) speed sensor defective
  5. Torque converter clutch piston defective
  6. Torque converter check valve defective
  7. Lock up shift valve defective
  8. Lock up control valve defective
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the A/T clutch pressure control solenoid valve C body gasket for wear and damage. If the A/T clutch pressure control solenoid valve C is stuck, inspect the CPC valves.
AT gear position indicator does not indicate shift lever positions
  1. Transmission range switch defective or out of adjustment
  2. Shift cable broken or out of adjustment
  3. Connection between shift cable and transmission or body is worn
  • Check the D5 indicator, and check for loose connectors.
  • Inspect the transmission range switch. If the transmission range switch is faulty, replace it. If the transmission range switch is out of adjustment, adjust it and the shift cable.
  • Check for a loose shift cable at the shift lever and the transmission control shaft.
Speedometer and odometer do not work Output shaft (countershaft) speed sensor defective Check the D5 indicator, and check for loose connectors.
Engine does not rev to high RPM, and the transmission upshifts at low RPM (engine at normal operating temperature) VTEC rocker arms defective Check the engine rocker arms.
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