Odd Electrical Issues... clock doesn't maintain time, etc

[asutherland]

The Cruiser has been recently plagued with several, seemingly unrelated, electrical issues. Things I have noticed,

- Clock doesn't maintain time. Sometimes. Will pick random times to show when I start the vehicle, sometimes.
- Cargo area dome light doesn't work. NO VOLTAGE to it. Checked all fuses, all are good. Main dome light works fine.
- Front e-locker light fades in and out on the dash. Very sure my front diff is NOT locked at the time lol.
- Rear e-locker light continues to flash even when it IS locked in the rear. Confirmed this.

Not having any issues with starting the truck, lights etc seem to work fine. I've checked the ground from battery to chassis which seems fine. Both batteries are less than a year old.

Ideas?

 

[TrickyT]

Most likely separate problems, but in addition to checking battery to chassis ground, check the battery to body grounds too. Clock times changing may be due to voltage spikes not getting suppressed because of bad filter capacitors on the clock board.

 

[asutherland]

While normally I'd agree, all symptoms started happening at the same time. Other than the battery to side of engine bay cable, do you know where any others are?

 

[Offroads4x4]

Start at the battery and clean all your connections using dielectric grease on them after. Follow the wires to your alt and clean it as well.

I think in the long run you problem is going to be a bad or dirty connection.

You may also want to clean your connection to your instrument cluster as well to eliminate it from the possibilities.

This would be my first starting point on the locker light. Start by cleaning with electrical cleaner all connections from the locker up. Be sure to use dielectric grease in the connections as you plug them back in. You may want to do the same to any other ones you can reach while under the rig at the same time. Who knows who's driven through water etc..... Over the years.

Next check and clean any grounds as mentioned above.

JM2C of ideas.

 

[asutherland]

Update. Front locker (that was fading in and out when it wasn't locked) - I took the connector off the locker motor, cleaned it and put dielectric grease in it. Reseated it, and so far so good... doesn't appear to be ghosting on at all. Haven't had that much run time since then though, but I'm hopeful.

Clock / lights on chime - Disconnected both batteries for a while, reconnected. Clock has been maintaining time properly and door chime sounds normal. So far so good.

Rear locker light (that would flash but never go solid) - I put rear of truck up on jack stands, locked the rear, and verified it was physically locked. I then disconnected the harness from the ball sensor. Jumpered the 2 wires on the harness, the dash light did not go solid. Checked resistance across the 2 pins on the ball sensor (when truck was definitely locked) - resistance was only a few ohms (expected). UNLOCKED the truck, checked resistance again... near infinity (not connected). Again expected. So the locker, the ball sensor appear fine. Something is wrong further up the line.

I then checked the connection all the way to the rear cross member. Where does the locker wiring go from there? I can see the front locker wiring... just goes up the axle and into the engine bay. But I can't find the rear wiring.

Rear dome light - According to the FSM elec diagrams, the rear dome light and the passenger dome light power sources are connected, via the 7.5 amp dome fuse. The passenger door light is getting 12.58 volts and works. The rear is getting 1.2 - ish volts and doesn't work. I checked the voltage using a separate wire directly to the negative terminal on the battery as well. Same. I also checked resistance between the ground on the light, and the negative battery terminal.. it's less than .5 ohm which is perfect - the ground is good. Something is wrong with the source wire.

The source wire for the rear dome light (cargo) is a blue/yellow or something. The source wire for the passenger dome light is black/white. So there's another junction in there somewhere. ANY IDEA where???? I partially pulled back some headliner (ugh) but can't see anything useful.

 

[asutherland]

Another update... the rear locker wiring, the cargo dome light, along with a couple door sensors and other stuff all go along the inside right hand side (USA driver side, JDM passenger side) near the footwell. Then through the firewall in the kick panel. My problem exists somewhere in the 10 or so inches of wiring loom from the grommet in the firewall to the fuse box. I can wiggle the oem wiring bundle, and my "Door open" dummy light on the dash works/doesn't work, as well as other weirdness.

Tomorrow I will unravel it all and try to determine where the break is.... sigh. At least that explains the rear dome light + rear locker sensor issue

 

[asutherland]

Another update (and new problem!)

I was wrong with the rear locker sensor issue. It was a separate issue. The locker sensor wiring from axle to body (on the rear of the truck) was damaged, causing a high resistance in the wire. I repaired the wire, and the sensor works perfectly now.

I did repair the factory splice of blue/yellow wire in the engine bay (right before it goes thru the grommet). The connection, which split the blue/yellow from the fuse box, into 2 blue/yellow wires - one goes to the rear dome and one goes to the front dome - was corroded and fell apart. After repairing I now have a full 12.58V on the rear dome.

HOWEVER. The "Door open" light on the dash doesn't work now. While I was fiddling with the harness, the light on the dash was flickering which I contributed to the fact that same blue/yellow pwr wire ran to the dash light.

AND. There is 7 volts on the centre dome light now, when in DOOR position. When ON position it works fine, with source wire 12.58V, but stick it on DOOR and shut the doors, the light stays on dimly and measures 7V. If you open a door, it lights properly.

EDIT: The source + DOOR wires measure 12.5V, but when you put the light in the circuit it downs to 7V. Source + GND (ON position) work normally.

Ideas?

EDIT: I disconnected both side kick panel connectors, where the sensors for the doors and rear hatch go through - to ensure there wasn't a semi-ground on one of the door sensors. Removing the sensors from the circuit made no difference on the 7V when on the DOOR position. (but of course doesn't light up fully now when the doors are open - as expected)

 

[landcrshr]

So here's what I was thinking (after our PM conversations). There is still a break somewhere in the blue/yellow wire, which accounts for no power to the warning lamp(s) in the cluster. The clock is now being powered through the dome light and a least one other light when the doors are closed as seen here in this theoretical drawing.

Of course this drawing is just to explain how this could be possible, it doesn't accurately represent the actual wiring in the vehicle, but should give you something to go on.

I think focusing on restoring DOME-circuit power the cluster will be the answer.

 

[asutherland]

Hmm, that could make sense for sure. To update the others... I am now experiencing these symptoms as well:

-Dome light glows dimly when on DOOR position, even with all doors closed (and I ensured the connectors were disconnected, ensuring no ground via faulty door striker switch)
-Disconnect clock, dome light stops glowing and functions properly
-Turn headlights on, dome light starts glowing dimly again while all doors are closed
-Automatic headlight off function (when open drivers door) doesn't work
-Door open (dummy light) on dash doesn't work (no pwr to connector - tested)
-Rear swingout (dummy light) on dash doesn't work (no pwr to connector - tested)
-Door open (with key in ign) doesn't chime

Now... does anyone have any idea where the blue/yellow pwr wire that feeds the gauge cluster joins with the blue/yellow dome light pwr wire? There is a 2 wire factory splice of the blue/yellow (taking 1 wire from fuse box and turning it into 2 wires) that happens just before the harness goes through the firewall (on the engine bay side). One wire feeds back to the rear cargo light, and the other feeds the main dome light. But I'm not sure where the cluster wire splices in.

 

[landcrshr]

Look for the "J3" junction connector shown here:

You would find it here (on a US model):

Happy hunting!

 

[asutherland]

Thanks dude! Do you have the rest of the image? Where's the top 3 blue/yellow go?

 

[landcrshr]

Schematic is for a '96 US model. The lines at the top go to the door courtesy lights (that you don't have) and the key cylinder light relay.