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Hi All,

I have a 93 YJ (4-Cyl) that makes a clicking noise in the engine compartment (in or near the fuse box) when the key is turned.

Originally it would click for a minute, followed by the check engine light coming on and then would start right up. It started taking longer and longer for the clicking noise to happen... The last time I tried the clicking noise came right on and didn't stop at all... Just kept clicking and wouldn't start. This eventually just drained the battery.

Thanks!  

does the clicking noise happen when you turn the key to the run position.. ???

or do you have to hold the key in the cranking position...

there are several things that can make a clicking noise..

the main relay for the fuel injection system

the starter relay.. the starter solenoid.. the starter..

there are other relays and stuff in that jeep.. i will have to dig through my jeep manual that i think covers that model.   but identifying clicks by looking at pictures...

can you clean the battery cables.  with hot water and a wire brush..


so.. clean the battery.. recharge it..  try again..

be sure to check the rest of the wires..

from the negative battery post to the body ground connection..  the small wire from the side..

down at the starter motor.. that the cable is clean and tightly attached to the top of the starter solenoid..

don't try to start it with a discharged battery..

you should be able to feel for what ever is clicking..  if so..describe it.. photograph it..  post the photographs to photobucket  its free..   when posted. hover the cursor over the image.. click on the 4th link down.. then paste that link here..

take some pictures of the battery area.. and the cables..  

Thanks for responding and the advice!

The battery is in good shape.
The terminals are clean and free of corrosion.

I replaced the ’Starter Relay’

Here is the events that followed:

Turned the key to on, engine light did NOT come on (I’ll explain more about this later).
Engine turned over, did not start.
The battery was being drained from attempted starts so we charged it.
When the key was turn to on, a low clicking started in the engine compartment.
The clicking got louder until it could be heard and when I felt the fuses (I have pictures), it was pulsing there.
When the clicking stopped, the Engine Light came on and the truck started (as it had done in the past).

The Starter was re-done in the past 5 years but seems to be okay!
 
Can you advise?

Thanks Again!  

I have posted pictures to Photobucket in ‘Wonderguide’  

see where the two wires are attached to the stud on the firewall above the heater core..  i would like you to take the nut off.. wire brush both sides of each terminal.. wire brush the stud and the back of the nut.. so its bright and shiny..



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touch your finger to the relays..   which one is clicking...   the fuel pump relay or the auto shut down relay...

or one of the others...



don't forget that the relay box is labeled in sort of a backwards way...

when reading the in lid diagram...  turn it so the fuses are on the proper side...

you will want to check out the SECOND one in from the engine side.. and the 5th one in from the engine side..

according to the image.. the order is

HORN

fuel pump

empty as you don't have ABS

empty as you don't have A/C

auto shut down relay.. this turns on all the fuel injection power under the hood..

starter relay..

empty
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on the left side of the battery in this image...  the battery cables coming from the positive terminal are RED...

one wire goes to the starter.. the other feeds down to the underside of the fuse/relay box...  disconnect both sides of the battery.. the fuse box should be easily moved and twisted over to access the area where the battery cables comes in on the left..




your pictures look like you got into deep water with that jeep...

you can gently remove the relays..   then with a pair of small screw drivers pry the guts out of the cube cover.. then inspect the contacts. make sure they are NOT burned .. you can also use a continuity tester on beep mode.. to test the contacts to verify that they actually close when the lever is pressed sightly...

 

Thanks Again!

Ok,
Brushed & Cleaned the 2 wires, nut, post. Reattached

Took apart the fuse box, removed the relays, opened them, checked them (no burn marks), cleaned the prongs, reinstalled them in fuse box.

Charged battery, tried to start jeep...No Go.

Pulsing coming from the ‘fuel pump’ & ‘auto shutdown’ relays!

Thanks!  

let me see if i can find a wiring diagram for the jeep..

see how those plug in..  when you get a pulsing ..

its almost always a dirty connection some place..

what happens.. solenoid coils require over about 8 volts to close on these..  when there is no load.. the voltage can come up to a full 12 volts..  but as you add a load.. by turning the key on..  the voltage drops do to the restriction .. when it drops below 8 volts.. the relays snap open.. reducing load.. the voltage can then rise and snap them closed again.. then the voltage drops and they open...

a better description slightly different..


think of using a spray nozzle on the garden hose..  

with the nozzle closed there is pressure in the hose.. no flow..  

if the valve on the hose is wide open..  when you squeeze the nozzle.. you get a nice full spray of water...

now if you turn the water almost completely off..  just a trickle..    with the nozzle closed..  the hose has pressure.. no flow..   when you open the nozzle.. you get a spray for a second.. then it drops to the same trickle the valve is restricting it to..  

the dirty . loose.. corroded connection is what you have.. where there is contact..  but its NOT enough to allow enough electrons through to power the circuit...

do you have a digital volt meter????

i will look for a diagram ...

be back..  

the area of this diagram you need to see is off to the right out of sight..  print it.. use colored markers to draw the colors on the circuits..    use dashed and dotted lines... not a solid line unless its a transparent color...


 

you will also want to print this second diagram...

 

a circuit tester might also come in handy... test light..

i am first taking that you have properly used a wire brush to clean the battery posts and the inside of the battery cable ends.. so they are nice and shiny...

hook the test light across the battery cables..  have somebody turn the key.. does the test light stay on solid bright when the relays are clicking???   solid bright is good...

with the test clip hooked to the negative battery post...

start probing both ends of every fuse...  with the key on.. see if you get bright solid light..

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in the upper diagram...

the fuel pump and shut down relays are in the upper right corner of the diagram..  

pay close attention to fuse number 5... fuse 5 in under the dashboard...  a 10 amp fuse.. it probably gets switched power from the ignition switch..  you might want to pull it and push it back in.. make sure that its making good contact...    that supplies power to the wht/yel wire.. white with a yellow stripe.. that feeds the relay coils positive voltage..   please probe fuse 5 while somebody attempts to crank the engine.. you should still get a steady bright light.. if you get a pulsing test light..  the problem is between the battery and the fuse block..  

the white/yellow wire feds the positive side of the relay coils...  it also feeds the ECM on pin 9... and its also on one of the pins of the diagnostic connector..    please don't go probing that connector with a test light unless you have identified which wire.. you don't want to probe a logic wire..  3 of the 5 are probably logic wires..


~~~~~~~~~~~~~~~~~~~~

the computer also gets power from fuse F1...  a 30 amp fuse. please be sure to check that also.. make sure that you get a bright bulb and steady brightness when the relays are clicking..


the computer gets grounded on two separate wires.. ECM pins 11 and 12..  i have to get into the jeep factory service info to see where they are grounded at..

most jeeps also have ground wires on the left lower corner of the bell housing and on the right lower corner of the bell housing...   do you see any wires on a bolt or stud down there???   perhaps the other end of the wire from the firewall...  you might want to take those apart and clean them...

more to come...  

Thanks for the diagrams!

I don’t have a volt meter though.

I managed to use a small nail-file-board and try to clean out the connectors. We tried again, but still no start and same pulsing in the 2 relays.

I assume the diagrams would be to try to locate where the problem originates from. Can I do anything else (with limited tools, I’m at my in-laws using their tools)?

Again, big THANKS!  

almost any auto parts store sells test lights.. circuit testers..  most sell a digital volt meter for under 20 bucks..

you will also need a wire brush..   i normally try to find a stainless steel wire tooth brush..  about 2 bucks at most hardware or paint stores..    the wooden handle ones are usually better..

target will have circuit testers in the automotive section. along with wire tooth brushes..  

walmart, sears, kmart,    scotch bright pads from the kitchen can be used..  but thrown away afterwards..


the problem is if the power is intermittent on the positive side or the negative side..

doe the headlights flash or anything else flash???

does this clicking happen when the key is in the on position.. or only when you try to crank the engine...

does the engine actually crank... ????

log in.. check messages to the left of where you log out at...  

Hi Wayne,

I just wanted to say “THANKS” again for all your help in trying to help me solve the 93 YJ electrical problems!

I traveled back to Alberta and left my brother-in-law with the information. I’m not sure if he has solved it all, but your help was much appreciated!

Take Care

Dino