Top 10 1999 Jeep Grand Cherokee Questions & Answers

The PCM has the voltage regulator inside it that controls the charge from the alternator to the battery, unlike older vehicles that have the voltage regulator directly on the alternator. Also there is a battery temperature sensor under the battery that the PCM uses to decide how much to send the battery. Possibilities; bad alternator, bad PCM, bad battery temp sensor, bad battery, and bad connections. Battery tests are easy check when fully charged should get around 12.5v then turn on headlights for 2 minutes and check again should still be around 12v. To test charging system start engine and test at bettery terminals should get 13-15v if not then something wrong with charging system take alternator to advance auto and they will test it for free if its good you are down to connections, PCM and battery temp sensor. test battery temp sensor at 75 to 80 degrees fahrenheit should get 9000-12000 ohms resistance (9k-12K ohms) if thats good check ground connections on vehicle body , connections on alternator, and plugs into pcm as well as the two above it (depending on model and year). If all that is good your PCM is bad get one on the internet preprogrammed for your vin number for $250 if you get one at the parts store it is $250 and then you have to get it programmed about another $80. You can also test the alternator your self by disconnecting the 3 tiny nuts and removing the connection from the field terminals (plastic piece with two terminals) and checking again at battery for 13-15v ( stay away from pulleys and belt,no loose clothing or long hair if you value your health). The PCM shorts the field connectors to regulate the voltage so removing that connector eliminates the PCM , battery temp sensor and the wire to and from them.

Alarm Module Reset Procedure
NOTE: This information applies to a Vehicle Theft Security System (VTSS) that was armed when the battery was disconnected and reconnected.
When the armed VTSS senses that the battery has been disconnected and reconnected, it enters its power-up mode. In the power-up mode the alarm system remains armed following a battery failure or disconnect. If the VTSS was armed prior to a battery disconnect or failure, the system will have to be actively or passively disarmed following a battery reconnection.
The power-up mode will also apply if the battery goes dead while the system is armed and battery jump-starting is attempted. The engine no-run feature will prevent the engine from starting until the alarm system has been actively or passively disarmed.
Passive disarming of the Vehicle Theft Security System (VTSS) occurs when the vehicle is unlocked using the key to unlock either front door or the lift gate. Active disarming of the VTSS occurs when the vehicle is unlocked by depressing the Unlock button of the Remote Keyless Entry (RKE) transmitter.
Once the alarm has been activated (horn sounding, lights flashing, and the engine no-run feature), either disarming method will deactivate the alarm.
Depressing the Panic button (if equipped) on the RKE transmitter will also disarm the VTSS, but the horn will sound and the lights will flash for about three minutes as part of the Panic feature. The horn and lights can be stopped by pressing any of the RKE transmitter's buttons or driving the vehicle above 15 mph.

For the Fuse Block, identification and description about even fuse, for your first step, review the ZJ-Secc-8W-Wiring-Diagrams (page 7, fig. 12).

I hope help you with this. Good luck (rated this).

The 1996 Jeep Grand Cherokee Laredo Anti-Theft System is equipped with Vehicle Theft Security System (VTSS). VTSS system monitors vehicle doors, hood, liftgate and ignition. If an attempt is made to enter or operate vehicle without proper disarming of system, vehicle horn will sound, headlights, taillights and parking lights will flash, and engine will be prevented from running.

The following wiring diagram and electronics circuit contains detail schematics of The 1996 Jeep Grand Cherokee Laredo Anti-Theft System. Herein you will find interconnection between electronics parts of the system such as body control module, auto headlamp light sensor. VTSS led, driver door module, passenger door module, cylinder lock switch, junction block, power distribution center, and grounding. Herein you will learn also how the Vehicle Theft Security System works, removal, installation, testing and troubleshooting procedures.

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Also, remember that here can find the Jeep Grand Cherokee Service & Repair Manual.
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Hi .. First I would remove the lamps, and try the brakes, then try again with the wiring harness disconnected from the housing, to see if you can isolate the problem to the lamps, the housing, or the wiring. If it is the wiring , then you will have to trace the harness back toward the front of the car looking for any place where the insulation on the wire has been damaged .

Hi, the mass air flow sensor is on the intake tube just before the throttle body. these sensors are extremely sensative. there is a special cleaner that you can purchase at parts stores.

On 4.7L the MAP sensor is located on the front of the intake manifold. An O-ring seals the sensor to the intake manifold.


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1. Disconnect electrical connector at sensor.
   
2. Clean area around MAP sensor.
   
3. Remove 2 sensor mounting bolts.
   
4. Remove MAP sensor from intake manifold.

its just taped into the harness you should be able to run a new one along side the harness

Grand Cherokee isnt have "fuel reset switch"; if you have a problem there, could be a fuse or wiring problem in the cricuit; also could be fuel pump itself. If you need other details, just ask, we have 1993-'98 Repair Manual.

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the transmission is over heated , check the fluid level and check that the cooling system is working correctly as there will be a trans fluid inter cooler which may not be operating correctly