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Obscure Product Knowledge Archive › Automotive › Jeep › XJ › AW4 Neutral Safety Switch Repair
The Jeep has an intermittent no-start condition.
A significant diagnostic clue is that rapidly moving the automatic transmission shifter back and forth may eventually cause the problem to disappear, allowing the Jeep to start and run normally.
Someone experiencing this problem may describe it as:
The problem was traced to the neutral safety switch on the AW4 automatic transmission.
The factory lubricant inside the neutral safety switch had become very sticky with age. This aged lubricant interfered with proper operation of the neutral safety switch.
Moving the shifter rapidly back and forth could temporarily restore switch operation, allowing the vehicle to start.
Cleaning the aged factory lubricant from the neutral safety switch and replacing it with fresh lubricant restored proper neutral safety switch operation in this documented repair.
The switch did not require replacement to correct this particular failure.
If an AW4-equipped Jeep Cherokee XJ has an intermittent no-start or no-crank condition and moving the transmission shifter back and forth causes the vehicle to start, the neutral safety switch should be investigated.
The switch itself may not necessarily have failed electrically. Aged and sticky internal lubricant can cause the switch to malfunction.
The AW4 neutral safety switch should be considered a serviceable maintenance item.
Cleaning and relubricating the switch can restore operation, but the lubricant may need to be replaced again in the future as the vehicle continues to age.
Relevant terms for this repair include:
This entry documents a firsthand, physically tested repair on a 1991 Jeep Cherokee XJ equipped with the AW4 automatic transmission.
It records the failure and repair observed on this vehicle. Similar symptoms can have other electrical or mechanical causes, so this repair should be used as a diagnostic reference rather than as proof that every XJ no-start condition is caused by the neutral safety switch.
This repair is part of the Obscure Product Knowledge Archive, a collection of firsthand repair results, tested fixes, parts information, compatibility findings, and hard-to-find technical information.