Weird Electrical Issues

[pipeliner_78]

Ok guys...I'm a newby to The Ranger Station and I have a few electrical issues. My ranger is a pieced together mutt. However I think that most of it including the engine is from 1990. It's a 2.9L V6, manual, 4x4, ext cab.

1. When I step on the brakes it automatically blows the fuse. Taillights, headlights, blinkers all work.(I think it is the brake switch)

2. When you turn the head lights on or off the radio goes off for a second. Plus when you have the lights on the truck goes into "high idle mode" It idles at 2500rpm.

3. Gas gauge is stuck on full.

4. Check oil and check engine light come on and off.(Oil is fine)

5. Not sure if this is electrical but the speedometer is 15mph off...It doesn't even register till ur in 2nd gear.

 

[Earl43P]

1. Quick way to rule out a brake lamp/socket short is to disconnect the tail light harness at the back of the bed, middle. Then press the brake pedal. If it still blows the fuse, inspect brake switch and the remainder of the wiring to that disconnect. Trailer harness connections are notorious for causing shorts.

2. Make sure you have a good chassis ground at the radiator support (driver side of the radiator) and it's connected to Bat - with the small wire.

3. Broken wire to the sender or bad connection at the top of the tank (an open wire will make it read full, a short will make it read empty).

4. Look at the side of the engine oil pan. There is a one wire connection to the oil level sender. If that wire rubs to ground anywhere, the Check Oil light will come on. Disconnecting that wire will help you determine if it's a rub/short or a bad level sender.

5. Speedo is driven by a gear and a cable.

 

[pipeliner_78]

Thank you very much...That was fast..LOL...I will take a look at those and see what happens.

 

[pipeliner_78]

Ok I forgot one....The temp gauge doesn't work....I did notice that the temp sender wasn't hooked up and was pretty narly looking so I replaced it. When I did It stays on Cold but if I take the wire off of it, It goes straight to hot....Is it the same principle as the Fuel gauge?

 

[Earl43P]

Short that sender wire to ground, then (briefly) turn the key on and see if the temp gage goes to full cold. If so, you may simply have a stuck open thermostat and the engine is over-cooling.

 

[pipeliner_78]

Short that sender wire to ground, then (briefly) turn the key on and see if the temp gage goes to full cold. If so, you may simply have a stuck open thermostat and the engine is over-cooling.

it is already at full cold and it doesn't move when I turn on the key....So do I still do that or what? I just put a brand new sender in it yesterday.

 

[pipeliner_78]

Ok I have more information about my electrical issues.. Ok guys this is nuts... Well I put a fuse in the fuse panel for the brakes and started trouble shooting... When I push the brake the truck idles up, when I turn on the blinkers it idles up, but when I turn on the hazards it idles back down and the turn signals don't work anymore... The also when when I push the brake pedal down the front turn signals get brighter right along with the brake lights.

 

[4.0B2]

check all grounds... at battery, motor, ecu, etc... all of them!

you don't have a bad battery or alternator do you? things act funny at low voltage..

 

[pipeliner_78]

check all grounds... at battery, motor, ecu, etc... all of them!

you don't have a bad battery or alternator do you? things act funny at low voltage..

No don't have a bad alt. or batt. Batt is brand new and alt tested good. Where exactly should all of my grounds be?

 

[Earl43P]

Most of your grounds (including exterior lights) are in the engine compartment.

Inner fenders, radiator support, Wiper motor mount bolt to head/intake, etc.

Turn signals will not operate when the hazard blinker is on.

Your lighting issue (Parking lamps get bright when brake is pressed) could be a bad rear lamp. Sometimes when the filament blows, one end of it will weld itself to the Parking Lamp filament, joining those two lights' circuits.