Interior-Exterior Thermometer

Hi folks, One of the things I got for Christmas in a clock/temperature monitor that tells you what the temperature inside the Jeep is and also what temperature is outside the jeep. It sticks with sticky velcro anywhere you want to stick it - I put mine over the glove box so my daughter has something to do . My question for the folks is this:

It comes with a lead on a long wire for the outside temp sensor and I am having an indecisive time coming up with a spot to stick it. The literature (the deep thought stuff on the packaging) suggests in the door frame, but on this Jeep the doors are off most of the summer as much as I can get away with. The idea here is it beeps when freezing to warn for black ice possibility. It needs to stay relatively dry and not be affected by motor heat. It has maybe 8 feet of wire. Suggestions? Thanks folks, Tomes

02 TJ
Reply to
Tomes
Loading thread data ...

Between the inside of the grill and the radiator is where the temperature sensors are generally installed.

Reply to
billy ray

I had mine screwed to the inside of the plastic on the front bumper cap. It got cooked by too much RF! I don't run that much power anymore. I was afraid I was going to cook the Jeep's ECM after the headlights would get real bright for a moment after I let off the key. Regulation is a quite a bit slower then on my AC Delco 120 amper in my big car.

Reply to
Scott in Baltimore

How about inside the vent, just in front of the winsheild?

Completely invisible - you wont see it, and it's out of the way.

Reply to
Jason Backshall

Thanks Billy Ray. 2 things - one is that I don't think the wire is long enough and two is that I agree that this is a real good spot since it sees the temperature unfettered by the vehicle. So this gets me thinking - can I extend this wire by cutting it and splicing in an extension? Does that muck up the calibration? I suppose I would at least need to use the same gauge wire. Talk to me on this if you please as I am dim on this type of stuff. Thanks, Tomes

Reply to
Tomes

Oh yeah another thing - is there a way to get it through the firewall? The sensor is about a half inch in diameter - if I cut the wire it will be only the wire diameter. Tomes

temperature

Reply to
Tomes

I like this idea too. Might this be affected by engine heat over time - just thinking out loud here... Then, how about getting the wire to there... Tomes

Reply to
Tomes

I advise against cutting the wire, as then you would have a metal to metal joint which is going to get oxidation on it sooner or later, and throw off the calibration. A half inch sensor is pretty big though. You can get it through the firewall using a half inch knock out punch, available at most electrical supply shops, a rubber grommet to fit the resulting hole, and a drill bit for your pilot hole. "Half inch" is the "nominal" size, and something a real half inch in diameter will easily fit through the resulting hole. The punch costs a few bucks, but once you see how it works, you will be using it to put holes in everything. If you look around under the dash, you might find a wiring harness you can piggy back to get through the fire wall, but I don't think any are in the ideal location.

Earle

Reply to
Earle Horton

There are probably access holes available that are blocked by plastic or rubber plugs.

The vent area might be adversely affected by heat gain from sunlight in addition to the heat gain from the roadbed.

Whether you can cut the wire is unknown to me. If it is actually just wire then perhaps you can cut and splice it but that may also affect the calibration.

Reply to
billy ray

There are probably access holes available that are blocked by plastic or rubber plugs.

The vent area might be adversely affected by heat gain from sunlight in addition to the heat gain from the roadbed. What color is the vehicle? My WJ, for example, is black and in sunlight the paint surface is often too hot to touch.

Whether you can cut the wire is unknown to me. If it is actually just wire then perhaps you can cut and splice it but that may also affect the calibration.

Reply to
billy ray

Thanks. I will go look for possible pathways tomorrow, we will see. Dark Green color. I am thinking a shady spot is best.

Anyone know about the cutting/extending the wire thing? Tomes

Reply to
Tomes

The GAUGE of the wire isn't terribly critical .................... but the TYPE of wire is crucial. The 'sensor' itself is a merely a thermistor (i.e. an electrical interface of two different compounds / metals) ... which changes electrical properties as temperature changes. One issue, even when extending the wire leads with the SAME wire type is the splicing. If you solder, for example, that can very much affect the properties of the thermistor 'circuit' (cuz you've essentially added another couple of electrical junctions / interfaces).

.... and if the kit comes with 8' of wire, you should easily be able to mount the thermistor in the grill and have the thermometer in the vicinity of the front dash.

Talk to me on this if you please as I am dim on this type of stuff.

Reply to
Rod's news

On my BMW, the probe is mounted in one of the aor ducts that direct cold air onto the brake rotors.

All you need to do is put it where it won't be affected by the hot exhaust system. Surely the probe is adequately sealed to deal with water splashing on it. I'd pick a spot where the rocks won't get it, if there is such a spot ...

Reply to
Jeff Strickland

Thanks Jeff. Right now I am running it under the carpet, out the back door and mounting it on the bottom of the 3rd brake light. We will see how that works out. It is in the elements and somewhat protected. Tomes

Reply to
Tomes

The one in our old Volvo was below the front bumper to pick up the road temperature. It went red at 32 to let you know to watch for black ice.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Reply to
Mike Romain

It's just that on the packaging it noted to keep the sensor out of the 'way of the car wash' or somesuch; it looks sealed enough though. Maybe the peril is that it falls off under water pressure spray, not that it will leak. Would the temperature be much different at these two elevations you think? This one audibly alarms at 32 degrees too for the black ice alert. Tomes

Reply to
Tomes

Heh, anywhere there is a material to dissimilar material junction, such as when a wire enters a plastic probe casing, there can be a leak. That is why you want to keep it away from pressure spray and harsh detergents. My feeling is that anywhere back of the vehicle is likely to be affected by exhaust or engine heat, but not by much. A few test drives should give you a feeling for whether the device is reading accurately or not.

Earle

Reply to
Earle Horton

The temperature on the road is different than the air temperature. A lot of traffic or thawed ground can keep the road surface wet/warm when the air temperature is below freezing and a hard frost can keep the road frozen when the air temperature has warmed up.

Sun also has a 'radical' affect on the surface temperature of a vehicle. So does your vehicle's heater. The rear door of our Cherokee can be frozen up and the vehicle's heater will eventually warm it up enough to melt.

Mike

Tomes wrote:

Reply to
Mike Romain

I'd guess that the "car wash" warning had more to do with it not getting broomed off by the RoboWash brushes.

There can be a fair bit of difference > It's just that on the packaging it noted to keep the sensor out of the 'way

Reply to
Lee Ayrton

Lee Ayrton did pass the time by typing:

FWIW, the outside sensor on the ZJ is located behind the front grill. One of the verticals blocks the sensor from direct rain and it's about

1" from the radiator. Works well there. The fan sucks outside air past the sensor so the radiator doesn't affect its reading.
Reply to
DougW

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.