Not a Camry; looking for troubleshooting advice, 88 Supra

88 Supra, NA (not turbo).

My temp guage went out this afternoon. It was working this AM, was working
at kunch, and was working until I stopped on the way home to get a cuppa
coffee.

Nothing. Dropped right down to the pin. I don't like driving without a
temp gauge, esp in a car noted for eating headgaskets.

Any idea what to look for? Can I apply a voltage somewhere to the
instrument cluster to get a reading?

Can I check a plug going to the inst. cluster to look for a voltage?

How can I check the sending unit?

Any ideas

--
In the grand scheme fo things...
What difference does it make?

Hachiroku wrote:[color=blue]
> 88 Supra, NA (not turbo).
>
> My temp guage went out this afternoon. It was working this AM, was working
> at kunch, and was working until I stopped on the way home to get a cuppa
> coffee.
>
> Nothing. Dropped right down to the pin. I don't like driving without a
> temp gauge, esp in a car noted for eating headgaskets.
>
> Any idea what to look for? Can I apply a voltage somewhere to the
> instrument cluster to get a reading?
>
> Can I check a plug going to the inst. cluster to look for a voltage?
>
> How can I check the sending unit?
>
> Any ideas
>
> --
> In the grand scheme fo things...
> What difference does it make?[/color]


Got a Haynes for it? Try changing the engine coolant temperature (ECT)
sensor?

If it's shot, your voltage will probably read 0.0 V ;)

On Mon, 10 Apr 2006 16:27:42 -0700, onehappymadman wrote:
[color=blue]
>
> Hachiroku wrote:[color=green]
>> 88 Supra, NA (not turbo).
>>
>> My temp guage went out this afternoon. It was working this AM, was working
>> at kunch, and was working until I stopped on the way home to get a cuppa
>> coffee.
>>
>> Nothing. Dropped right down to the pin. I don't like driving without a
>> temp gauge, esp in a car noted for eating headgaskets.
>>
>> Any idea what to look for? Can I apply a voltage somewhere to the
>> instrument cluster to get a reading?
>>
>> Can I check a plug going to the inst. cluster to look for a voltage?
>>
>> How can I check the sending unit?
>>
>> Any ideas
>>
>> --
>> In the grand scheme fo things...
>> What difference does it make?[/color]
>
>
> Got a Haynes for it? Try changing the engine coolant temperature (ECT)
> sensor?
>
> If it's shot, your voltage will probably read 0.0 V ;)[/color]

Unfortunately, I have Haynes for the other three Toyotas I have...

--
In the grand scheme fo things...
What difference does it make?

"Hachiroku" <Trueno@ae86.GTS> wrote in message
news:UGA_f.3472$ee6.2059@trndny01...[color=blue]
> 88 Supra, NA (not turbo).
>
> My temp guage went out this afternoon. It was working this AM, was working
> at kunch, and was working until I stopped on the way home to get a cuppa
> coffee.
>
> Nothing. Dropped right down to the pin. I don't like driving without a
> temp gauge, esp in a car noted for eating headgaskets.
>
> Any idea what to look for? Can I apply a voltage somewhere to the
> instrument cluster to get a reading?[/color]

You'll need a wiring diagram to know which instrument cluster pin to
energize.
[color=blue]
>
> Can I check a plug going to the inst. cluster to look for a voltage?[/color]

Again, you'll need a wiring diagram to know which pin to check.
[color=blue]
>
> How can I check the sending unit?
>[/color]

First, see if the wires to the sending unit (I think it is on or near the
thermostat housing) is connected and the connector didn't corrode off. If
it is a 2-wire unit, then you should have 12 volts going in and varying
voltage coming out, depending on coolant temp. If you have 0 out, then the
sender is bad. You may be able to confirm by cannibalizing a sender from
one of your other Toyotas.

Note the color and tracer for the wire for the variable side of the sender.
It is probably the same color going into the instrument cluster. If you are
getting voltage out of the sender, you can check for the same voltage at the
cluster. If the voltage is not the same, then you may have a cut in the
wire or a loose connection between the sender and the cluster. If this is
the case, finding the fault in the wire or connection is going to be a big
job. Just run another wire from the sender to the cluster and use a Scotch
lock at each end if you don't feel like soldering.
--

Ray O
(correct punctuation to reply)

"Ray O" <rokigawa@tristarassociatesDOTcomn> wrote in message
news:666dd$443b3cd7$180fead6$29597@msgid.meganewsservers.com...[color=blue]
>
> "Hachiroku" <Trueno@ae86.GTS> wrote in message
> news:UGA_f.3472$ee6.2059@trndny01...[color=green]
>> 88 Supra, NA (not turbo).
>>
>> My temp guage went out this afternoon. It was working this AM, was
>> working
>> at kunch, and was working until I stopped on the way home to get a cuppa
>> coffee.
>>
>> Nothing. Dropped right down to the pin. I don't like driving without a
>> temp gauge, esp in a car noted for eating headgaskets.
>>
>> Any idea what to look for? Can I apply a voltage somewhere to the
>> instrument cluster to get a reading?[/color]
>
> You'll need a wiring diagram to know which instrument cluster pin to
> energize.
>[color=green]
>>
>> Can I check a plug going to the inst. cluster to look for a voltage?[/color]
>
> Again, you'll need a wiring diagram to know which pin to check.
>[color=green]
>>
>> How can I check the sending unit?
>>[/color]
>
> First, see if the wires to the sending unit (I think it is on or near the
> thermostat housing) is connected and the connector didn't corrode off. If
> it is a 2-wire unit, then you should have 12 volts going in and varying
> voltage coming out, depending on coolant temp. If you have 0 out, then
> the sender is bad. You may be able to confirm by cannibalizing a sender
> from one of your other Toyotas.
>
> Note the color and tracer for the wire for the variable side of the
> sender. It is probably the same color going into the instrument cluster.
> If you are getting voltage out of the sender, you can check for the same
> voltage at the cluster. If the voltage is not the same, then you may have
> a cut in the wire or a loose connection between the sender and the
> cluster. If this is the case, finding the fault in the wire or connection
> is going to be a big job. Just run another wire from the sender to the
> cluster and use a Scotch lock at each end if you don't feel like
> soldering.
> --
>
> Ray O
> (correct punctuation to reply)[/color]

Thanks Ray!

But it seems to have fixed itself...sorta.

Started up this morning, and the gauge started working fine. All the way
from GFLD to Bratt.
Stopped for a cup of coffee, no tmep gauge, then it flickered, died, and
shot up to the proper position.
So, either a loose wire, a bad connection or a sender on the way out.

I did /sort of/ wash the engine Sunday, so there may be some water in the
system somewhere...

"Hachiroku" <Trueno@ae86.GTS> wrote in message
news:16N_f.9819$rm3.9619@trndny06...[color=blue]
>
> "Ray O" <rokigawa@tristarassociatesDOTcomn> wrote in message
> news:666dd$443b3cd7$180fead6$29597@msgid.meganewsservers.com...[color=green]
>>
>> "Hachiroku" <Trueno@ae86.GTS> wrote in message
>> news:UGA_f.3472$ee6.2059@trndny01...[color=darkred]
>>> 88 Supra, NA (not turbo).
>>>
>>> My temp guage went out this afternoon. It was working this AM, was
>>> working
>>> at kunch, and was working until I stopped on the way home to get a cuppa
>>> coffee.
>>>
>>> Nothing. Dropped right down to the pin. I don't like driving without a
>>> temp gauge, esp in a car noted for eating headgaskets.
>>>
>>> Any idea what to look for? Can I apply a voltage somewhere to the
>>> instrument cluster to get a reading?[/color]
>>
>> You'll need a wiring diagram to know which instrument cluster pin to
>> energize.
>>[color=darkred]
>>>
>>> Can I check a plug going to the inst. cluster to look for a voltage?[/color]
>>
>> Again, you'll need a wiring diagram to know which pin to check.
>>[color=darkred]
>>>
>>> How can I check the sending unit?
>>>[/color]
>>
>> First, see if the wires to the sending unit (I think it is on or near the
>> thermostat housing) is connected and the connector didn't corrode off.
>> If it is a 2-wire unit, then you should have 12 volts going in and
>> varying voltage coming out, depending on coolant temp. If you have 0
>> out, then the sender is bad. You may be able to confirm by cannibalizing
>> a sender from one of your other Toyotas.
>>
>> Note the color and tracer for the wire for the variable side of the
>> sender. It is probably the same color going into the instrument cluster.
>> If you are getting voltage out of the sender, you can check for the same
>> voltage at the cluster. If the voltage is not the same, then you may
>> have a cut in the wire or a loose connection between the sender and the
>> cluster. If this is the case, finding the fault in the wire or
>> connection is going to be a big job. Just run another wire from the
>> sender to the cluster and use a Scotch lock at each end if you don't feel
>> like soldering.
>> --
>>
>> Ray O
>> (correct punctuation to reply)[/color]
>
> Thanks Ray!
>
> But it seems to have fixed itself...sorta.
>
> Started up this morning, and the gauge started working fine. All the way
> from GFLD to Bratt.
> Stopped for a cup of coffee, no tmep gauge, then it flickered, died, and
> shot up to the proper position.
> So, either a loose wire, a bad connection or a sender on the way out.
>
> I did /sort of/ wash the engine Sunday, so there may be some water in the
> system somewhere...[/color]

Check where the harness plugs into the sender first and carefully bend the
tab in the female side of the connector carefully if it is loose.
--

Ray O
(correct punctuation to reply)

"Ray O" <rokigawa@tristarassociatesDOTcomn> wrote in message
news:3ef$443bdeaa$44a4a10d$2180@msgid.meganewsservers.com...[color=blue]
>
> "Hachiroku" <Trueno@ae86.GTS> wrote in message
> news:16N_f.9819$rm3.9619@trndny06...[color=green]
>>
>> "Ray O" <rokigawa@tristarassociatesDOTcomn> wrote in message
>> news:666dd$443b3cd7$180fead6$29597@msgid.meganewsservers.com...[color=darkred]
>>>
>>> "Hachiroku" <Trueno@ae86.GTS> wrote in message
>>> news:UGA_f.3472$ee6.2059@trndny01...
>>>> 88 Supra, NA (not turbo).
>>>>
>>>> My temp guage went out this afternoon. It was working this AM, was
>>>> working
>>>> at kunch, and was working until I stopped on the way home to get a
>>>> cuppa
>>>> coffee.
>>>>
>>>> Nothing. Dropped right down to the pin. I don't like driving without a
>>>> temp gauge, esp in a car noted for eating headgaskets.
>>>>
>>>> Any idea what to look for? Can I apply a voltage somewhere to the
>>>> instrument cluster to get a reading?
>>>
>>> You'll need a wiring diagram to know which instrument cluster pin to
>>> energize.
>>>
>>>>
>>>> Can I check a plug going to the inst. cluster to look for a voltage?
>>>
>>> Again, you'll need a wiring diagram to know which pin to check.
>>>
>>>>
>>>> How can I check the sending unit?
>>>>
>>>
>>> First, see if the wires to the sending unit (I think it is on or near
>>> the thermostat housing) is connected and the connector didn't corrode
>>> off. If it is a 2-wire unit, then you should have 12 volts going in and
>>> varying voltage coming out, depending on coolant temp. If you have 0
>>> out, then the sender is bad. You may be able to confirm by
>>> cannibalizing a sender from one of your other Toyotas.
>>>
>>> Note the color and tracer for the wire for the variable side of the
>>> sender. It is probably the same color going into the instrument cluster.
>>> If you are getting voltage out of the sender, you can check for the same
>>> voltage at the cluster. If the voltage is not the same, then you may
>>> have a cut in the wire or a loose connection between the sender and the
>>> cluster. If this is the case, finding the fault in the wire or
>>> connection is going to be a big job. Just run another wire from the
>>> sender to the cluster and use a Scotch lock at each end if you don't
>>> feel like soldering.
>>> --
>>>
>>> Ray O
>>> (correct punctuation to reply)[/color]
>>
>> Thanks Ray!
>>
>> But it seems to have fixed itself...sorta.
>>
>> Started up this morning, and the gauge started working fine. All the way
>> from GFLD to Bratt.
>> Stopped for a cup of coffee, no tmep gauge, then it flickered, died, and
>> shot up to the proper position.
>> So, either a loose wire, a bad connection or a sender on the way out.
>>
>> I did /sort of/ wash the engine Sunday, so there may be some water in the
>> system somewhere...[/color]
>
> Check where the harness plugs into the sender first and carefully bend the
> tab in the female side of the connector carefully if it is loose.
> --
>
> Ray O
> (correct punctuation to reply)[/color]

I don't know why sometimes I lose my 'confidence'. Perhaps sometimes I just
need a gantle 'nudge'.

I was doing the usual 'maintenence' on a car this old this AM, check the oil
and other fluid levels and just give it a general once-over under the hood,
and I looked at the thermostat housing. Then I saw the connection, about 1/3
to 1/2 off the lug, and the lug kind of a sickly green color. I pulled the
connector off, pushed it on all the way, pulled it off and fully reconnected
it again.

No problemo! Thanks for the 'nudge'!

"Hachiroku" <Trueno@ae86.GTS> wrote in message
news:o4a%f.5344$qB4.4294@trndny07...[color=blue]
>[/color]
<snipped>[color=blue][color=green]
>>
>> Check where the harness plugs into the sender first and carefully bend
>> the tab in the female side of the connector carefully if it is loose.
>> --
>>
>> Ray O
>> (correct punctuation to reply)[/color]
>
> I don't know why sometimes I lose my 'confidence'. Perhaps sometimes I
> just need a gantle 'nudge'.
>
> I was doing the usual 'maintenence' on a car this old this AM, check the
> oil and other fluid levels and just give it a general once-over under the
> hood, and I looked at the thermostat housing. Then I saw the connection,
> about 1/3 to 1/2 off the lug, and the lug kind of a sickly green color. I
> pulled the connector off, pushed it on all the way, pulled it off and
> fully reconnected it again.
>
> No problemo! Thanks for the 'nudge'![/color]
You may want to wipe the green slime off the tab and apply some fresh
dielectric grease.

Happy motoring!
--

Ray O
(correct punctuation to reply)

This is not related to your Temp guage problem but I would like to
know if your fog lights are burnt out will that cause the warning
light on the gauge counsole to illuminate.
I just got the 88 Supra a few weeks ago. and notice I can't get the
light to go off. i have replaced all burnt out lights except the fog
Lights. At first the light just stayed on but since I replaced all the
bad bulbs except the fog lights it when I start the car it will stay
off then after about 5 minutes it will come on again.

On Mon, 10 Apr 2006 22:07:48 GMT, Hachiroku <Trueno@ae86.GTS> wrote:
[color=blue]
>88 Supra, NA (not turbo).
>
>My temp guage went out this afternoon. It was working this AM, was working
>at kunch, and was working until I stopped on the way home to get a cuppa
>coffee.
>
>Nothing. Dropped right down to the pin. I don't like driving without a
>temp gauge, esp in a car noted for eating headgaskets.
>
>Any idea what to look for? Can I apply a voltage somewhere to the
>instrument cluster to get a reading?
>
>Can I check a plug going to the inst. cluster to look for a voltage?
>
>How can I check the sending unit?
>
>Any ideas[/color]