Dash improvement

[Andy4639]

I had some issues with my dash so I decided it was time to look at it.
I also wanted to mount the new delay wiper mode also while I had the dash out. I got the brake light working and found my problem with the temp gauge and it wasn't in the dash it was out in the engine bay. The spade connector had come apart.
I got the delay wiper mod done to while I had it out. Not bad at all for a good nights work.
I still can't figure out why the oil and water temp go up when I pull the lights on though. Oh well at least it's all working again.

[brad_man_72]

The gages move when you turn on the lights because there's a voltage drop. Adding a relay to your headlights might help.

[Andy4639]

Originally Posted by brad_man_72

The gages move when you turn on the lights because there's a voltage drop. Adding a relay to your headlights might help.

Nope not the problem. Have relays installed and the gauges are going up not down. The volt gauge has a constant 14 volts on it. They go up with just the park lights on also. I took a jumper and grounded the headlight switch with the dash out but hooked up and it didn't change it.
Hawks put a ground from motor to cab wall and I added a motor to frame ground yesterday myself. Everything works fine just has that little gain when the lights come on so I know it's in the lighting wiring but where is the ?

[truckster]

It may or may not have anything to do with your problem, but the first place I check when dealing with electrical issues is grounding. Check battery to chassis, battery to body, body to chassis, under-dash, etc.

[Andy4639]

Originally Posted by truckster

It may or may not have anything to do with your problem, but the first place I check when dealing with electrical issues is grounding. Check battery to chassis, battery to body, body to chassis, under-dash, etc.

I'm going to add a cab to frame ground to. Just to make sure it's all covered. A little more background on this just so if the right person see's this they may klick on something. I used the factory gauge cluster with Speed hut gauges(plastic) that just has the plastic collar holding them in place with all the grounds ran to the main ground in the back of the panel.

[Andy4639]

Got the cab to frame ground cable mounted but no change in the way things work. Still have that little increase in oil and water when I pull on the parking lights are headlights. None of the other gauges are effected by this and the volts stay at 14 on the gauge. My scan gauge say the same thing 14 volts and it runs off the computer reading.

[engineer_gregh]

Maybe a bad light switch?

[Andy4639]

Originally Posted by engineer_gregh

Maybe a bad light switch?

I can't see how it would be bad when everything works correctly though.

[engineer_gregh]

I hate electrical gremlins. The switch is an easy thing to try and one more thing to eliminate in troubleshooting the problem.

[Andy4639]

Originally Posted by engineer_gregh

I hate electrical gremlins. The switch is an easy thing to try and one more thing to eliminate in troubleshooting the problem.

Can you explain to me what else I can do to see if the head light switch is the problem.
I stated I put a ground wire to it and it didn't make any differance so what else can I do to check it. The lights all work correctly also.

[engineer_gregh]

Try another switch. If you need one I have a spare I'll send you.

[VetteVet]

Here's a theory.
When you pull on the lights you get a voltage drop which is sensed by the voltage regulator in your alternator. That causes the alternator to kick up the voltage output which causes a tiny surge in the positive circuit of the truck. Higher voltage to the gauges will overcome the resistance in the gauges and show a higher reading on them until the alternator output levels out.

This would be more pronounced if the regulator was the old external type.

I would test this by turning off the lights and disconnecting the alternator small plug so that it would not charge. You'd be on battery voltage alone. Then turn on the lights and you might see a slight drop in the gauge readings but if they didn't increase with the alternator out of the equation, You might have your answer.

[ETsC10]

MOVING TO ELECTRICAL....

Ellen

[Andy4639]

I spent most of last Sunday going over all the dash stuff and I fixed several problems that I had. + installing the delay wiper stuff. I had the dash out that's why I was checking it. I used jumpers to ground the switches and the dash itself even with the one ground still hooked up + the ground in the bulk connector. I couldn't see any differances so I assume that it's else where in the electrical system. Where though is the $100.00 question.

VetteVet.
with the computer running the alternator now since the 6.0LSx motor install I'm not sure if I want to disconnect it while it's running. I have herd this can cause computer failures so not really wanting to try that at this point and time.
The increase seems to have gotten less since I added the 2 new grounds to the cab and motor but not real sure that's what did it.

[VetteVet]

I missed the part about the computer running the alternator so I agree with you. It's not worth taking the chance. I meant to ask you what the readings increase to, and do they stay constant or drop back down in a few seconds?

Both your gauges rely on sender grounding to the engine block. I don't see where you have your negative battery cable grounded. It should always go to the engine block for the best continuity for the starter and alternator and the rest of the grounds can come off the block.

[Andy4639]

Originally Posted by VetteVet

I missed the part about the computer running the alternator so I agree with you. It's not worth taking the chance. I meant to ask you what the readings increase to, and do they stay constant or drop back down in a few seconds?

Both your gauges rely on sender grounding to the engine block. I don't see where you have your negative battery cable grounded. It should always go to the engine block for the best continuity for the starter and alternator and the rest of the grounds can come off the block.

The battery ground is to the front side of motor.
The gauges are now only going up a little not like before. Before the water and oil would peg out! Now they are just moving a little and will stay like that until you turn the lights off and as soon as you do they go back down which if they don't get any worse I can live with it. I added another frame to motor and frame to cab ground and it already had the cab to motor and motor to battery so I hope this has it some what fixed for now. Maybe some day while I'm doing another mod on it I will run across the full fix for it.
Oh the voltage gauge never moves it stays a good 14 volts all the time.
As always your help is greatly appericated as is everyone elses.