..Fusible Link What gauge wire do I need to use for the main fusible link in a 2000 jeep cherokee?

A fusible link is a short piece of insulated low-voltage cable within an automotive wiring harness that is designed to protect the harness in applications where a fuse is unsuitable. In an extreme current overload situation, the conductor within the link is melted while the ensuing flame and spark is contained within the link's insulation.

Fusible links are not rated in amps like fuses because each installation is unique and designed to meet specific circuit protection requirements.

The automotive service industry recommends using the same gauge and length as the blown fusible link after the cause of failure is corrected.

Typically, a given harness segment is protected by a fusible link that is four gauge numbers smaller. A 14-gauge wire would be protected by an 18-gauge fusible link. A 6-gauge wire would be protected by a 10-gauge link, and so on. Odd number wire gauge sizes like 19, 15, 13 and 11 are counted when sizing a link. The length of a fusible link should not exceed 9".

In general, a fusible link should never be used to replace an automotive fuse unless authorized by a vehicle factory service bulletin. Likewise, never replace a fusible link with an automotive fuse.

Fusible links are used in most starting circuit applications. For more technical info on fusible links, visit www.sae.org

The dealer or a parts store (if they can order it) would know the necessary rating of the fusible link-the color code may also tell the correct amperage and gauge. If possible, might help if you take it with you when ordering a new one. Fusible links are cut out and replaced.

There should be 2 white wires coming from the alternator. There is a splice where it will go into 1 wire then into the fusible link. If the fusible link is not burned, simply match the gauge wire coming from it. You should never use anything smaller in diameter than 10 gauge wire for the charging system. If you want to replace the fusible link, you can run separate white wires from the alternator to the positive battery post with individual fuses or fusible links. I would recommend each wire have its own Maxi fuse holder with a fuse no less than 60 amps each.

The orange/light blue wire is connected to the red (positive) wire from the battery, through a fusible link (or two links depending on engine size) to pin #3 of the voltage regulator at the alternator. The fusible link will be in the harness so you may have to disassemble the harness. The fusible link is probably blown. This was probably caused by the defective alternator/regulator assembly.

According to my diagram, it appears to go from the red batt wire to a gray 12 gauge fusible link, into a brown 18 gauge link, then turns into the orange/light blue wire and to the alternator.

(A fusible link is a piece of wire that acts like a fuse and will burn out, opening the circuit when amperage above its rating. This protects the circuit and lessens the chance of fire).

Good luck, please ask if you need more info.

check wire and connections than battery may not be taking charge

Fusible Links

The engine compartment wiring harness has several fusible links. The same size wire with a special hypalon insulation must be used when replacing a fusible link.
The links are located in the following areas:

1. A molded splice at the starter solenoid Bat terminal, a 14 gauge red wire.
   
2. A 16 gauge red fusible link at the junction block to protect the unfused wiring of 12 gauge or larger wire. This link stops at the bulkhead connector.
   
3. The alternator warning light and field circuitry is protected by a 20 gauge red wire fusible link used in the battery feed to voltage regular #3 terminal. The link is installed as a molded splice in the circuit at the junction block.
   
4. The ammeter circuit is protected by two 20 gauge fusible links installed as molded splices in the circuit at the junction block and battery to starter circuit.
   

Other things it MIGHT be are the ignition switch, located on top of the steering column:


The other thing it MIGHT be is a faulty ignition cylinder (where your key goes into to start the K10).

Check the wire harness on the steering column also.

i would try the crank sensor they are known for no start problems on jeeps

use a 14 gauge link for a 30 amp requirement.

http://bbbind.com/free_tsb.html

Jeep got rid of Fusible links by 1999. All the fuses that in the past would be Fusible Links are now in the Power Distribution Center in the engine, as Maxi-Fuses. However you could have an after market modification that would include a Fusible Link. That said, make sure you have a good charge on the battery before starting, it doesn't seem like a big deal....but it could make a difference.