Allison

Main code 45 indicates the ECU has detected either an open circuit condition in a solenoid coil or the wiring to that solenoid. The DO NOT SHIFT response is activated when this code is detected and all solenoids are turned off. Neutral start is inoperable.

If solenoid resistance is about 1?2 Ohms, a short-to-ground code may not be set but could cause a burned-out solenoid driver in the ECU. Replace the solenoid when this occurs (see appropriate transmission Service Manual for replacement procedure). If the solenoid driver is burned out, 69 XX codes will be set. See the troubleshooting procedure for 69 XX codes.

Main code 45 indicates the ECU has detected either an open circuit condition in a solenoid coil or the wiring to that solenoid. The DO NOT SHIFT response is activated when this code is detected and all solenoids are turned off. DO NOT SHIFT light is not illuminated.

If solenoid resistance is about 1?2 Ohms, a short-to-ground code may not be set but could cause a burned-out solenoid driver in the ECU. Replace the solenoid when this occurs (see appropriate transmission Service Manual for replacement procedure). If the solenoid driver is burned out, 69 XX codes will be set. See the troubleshooting procedure for 69 XX codes.

Main code 45 indicates the ECU has detected either an open circuit condition in a solenoid coil or the wiring to that solenoid. The DO NOT SHIFT response is activated when this code is detected and all solenoids are turned off. DO NOT SHIFT light is not illuminated.

If solenoid resistance is about 1?2 Ohms, a short-to-ground code may not be set but could cause a burned-out solenoid driver in the ECU. Replace the solenoid when this occurs (see appropriate transmission Service Manual for replacement procedure). If the solenoid driver is burned out, 69 XX codes will be set. See the troubleshooting procedure for 69 XX codes.

Main code 45 indicates the ECU has detected either an open circuit condition in a solenoid coil or the wiring to that solenoid. The DO NOT SHIFT response is activated when this code is detected and all solenoids are turned off. DO NOT SHIFT light is not illuminated.

If solenoid resistance is about 1?2 Ohms, a short-to-ground code may not be set but could cause a burned-out solenoid driver in the ECU. Replace the solenoid when this occurs (see appropriate transmission Service Manual for replacement procedure). If the solenoid driver is burned out, 69 XX codes will be set. See the troubleshooting procedure for 69 XX codes.

Main code 45 indicates the ECU has detected either an open circuit condition in a solenoid coil or the wiring to that solenoid. The DO NOT SHIFT response is activated when this code is detected and all solenoids are turned off. DO NOT SHIFT light is not illuminated.

If solenoid resistance is about 1?2 Ohms, a short-to-ground code may not be set but could cause a burned-out solenoid driver in the ECU. Replace the solenoid when this occurs (see appropriate transmission Service Manual for replacement procedure). If the solenoid driver is burned out, 69 XX codes will be set. See the troubleshooting procedure for 69 XX codes.

Main code 51 indicates a failed offgoing ratio test. Low?1 upshift

An offgoing ratio test occurs during a shift and uses turbine and output speed sensor readings to calculate the ratio between them. The calculated speed sensor ratio is then compared to the programmed speed sensor ratio of the commanded range. After a shift is commanded, the ECU, after a period of time, expects the old ratio to be gone. If the ratio does not change properly, the ECU assumes the offgoing clutch did not release. The shift is retried if conditions still exist to schedule the shift. If the second shift is not successfully completed, Code 51 XX is set and the ECU returns the transmission to the previous range. Additional codes could be logged for other shifts where ?X? indicates the range from and ?Y? indicates the range to.

Main code 51 indicates a failed offgoing ratio test. 1?Low downshift

An offgoing ratio test occurs during a shift and uses turbine and output speed sensor readings to calculate the ratio between them. The calculated speed sensor ratio is then compared to the programmed speed sensor ratio of the commanded range. After a shift is commanded, the ECU, after a period of time, expects the old ratio to be gone. If the ratio does not change properly, the ECU assumes the offgoing clutch did not release. The shift is retried if conditions still exist to schedule the shift. If the second shift is not successfully completed, Code 51 XX is set and the ECU returns the transmission to the previous range. Additional codes could be logged for other shifts where ?X? indicates the range from and ?Y? indicates the range to.

Main code 51 indicates a failed offgoing ratio test. 1?2 upshift

An offgoing ratio test occurs during a shift and uses turbine and output speed sensor readings to calculate the ratio between them. The calculated speed sensor ratio is then compared to the programmed speed sensor ratio of the commanded range. After a shift is commanded, the ECU, after a period of time, expects the old ratio to be gone. If the ratio does not change properly, the ECU assumes the offgoing clutch did not release. The shift is retried if conditions still exist to schedule the shift. If the second shift is not successfully completed, Code 51 XX is set and the ECU returns the transmission to the previous range. Additional codes could be logged for other shifts where ?X? indicates the range from and ?Y? indicates the range to.

Main code 51 indicates a failed offgoing ratio test. 2?1 downshift

An offgoing ratio test occurs during a shift and uses turbine and output speed sensor readings to calculate the ratio between them. The calculated speed sensor ratio is then compared to the programmed speed sensor ratio of the commanded range. After a shift is commanded, the ECU, after a period of time, expects the old ratio to be gone. If the ratio does not change properly, the ECU assumes the offgoing clutch did not release. The shift is retried if conditions still exist to schedule the shift. If the second shift is not successfully completed, Code 51 XX is set and the ECU returns the transmission to the previous range. Additional codes could be logged for other shifts where ?X? indicates the range from and ?Y? indicates the range to.