[x300] Heated window washers sensor

X300
1

Got a question about the heated washers and related sensor. It
would seem that the sensor in the passenger side brake duct is
missing in my car. Can’t be sure it was ever there since I’ve owned
it. The harness is there, but no sensor. My understanding of that
sensor is it controls when the washer heaters are on, but I also
recall reading somewhere about that sensor also having something to
do with the seat heaters and air intake for the engine. True
statement? My seat heaters seem to heat just fine and get rather
hot and shut off after a time. Don’t know if the washers heat or
anything in the air intake. Does anyone know if the ‘‘open’’ circuit
defaults everything on or off? Does anyone have source for that
part? Do you think it would be possible to rig something from an
electronics store to replace the sensor?

http://www.jag-lovers.org/v.htm?1264908862--
Shawn X300 1995 Vanden Plas 4.0L
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–

2

In reply to a message from islandladd sent Sun 5 Dec 2010:

Try turning on the ignition to II, and testing for voltage at the
washer jet connector and see if you get 12v–
The original message included these comments:

Got a question about the heated washers and related sensor. It

–
UK. XJR 2001 Pacific Blue
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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3

In reply to a message from Andy K sent Mon 6 Dec 2010:

Thanks for the reply. Checked for voltage at the brake duct
connector and at the washer jets with key on/off, climate control
on/off, seat heaters on/off etc. Nothing. Tried joining the
terminals of the connector for the temperature sensor, but still
nothing at the jets. Any ideas?–
The original message included these comments:

Try turning on the ignition to II, and testing for voltage at the
washer jet connector and see if you get 12v

–
Shawn X300 1995 Vanden Plas 4.0L
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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4

In reply to a message from islandladd sent Thu 9 Dec 2010:

Interesting. Generally on other cars with heated jets they are
powered all the time the ignition is on. (they may have internal
heat regulation).

I do vagely recall someone saying they are controlled via the ext.
temp. sensor (and was surprised).
Maybe:
a) It is.
b) Maybe not, and a fuse has blown somewhere.

Either way I doubt short circuiting the sensor connector is going
to help. It’s just going to change it from one invalid reading to
another invalid reading and hence turn off any heat jet supply (if
it does control the heated jets)–
The original message included these comments:

Thanks for the reply. Checked for voltage at the brake duct
connector and at the washer jets with key on/off, climate control
on/off, seat heaters on/off etc. Nothing. Tried joining the
terminals of the connector for the temperature sensor, but still
nothing at the jets. Any ideas?

–
UK. XJR 2001 Pacific Blue
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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5

In reply to a message from Andy K sent Thu 9 Dec 2010:

Checked the fuse in the right heal box for the heated jets and it
was fine. I was never aware that they operated any other way than
off the sensor. I think the X300 book says they operate at
temps<24 C Wish I could find a way to power them up. Seems like
it would be alot easier than trying to find that sensor
somewhere… I tried joining at the sensor connector just
figuring that the sensor basically just completes a circuit at a
certain temp turning on the jet heaters. I guess not, or I’m
missing something.–
The original message included these comments:

Interesting. Generally on other cars with heated jets they are
powered all the time the ignition is on. (they may have internal
heat regulation).
I do vagely recall someone saying they are controlled via the ext.
temp. sensor (and was surprised).
Maybe:
a) It is.
b) Maybe not, and a fuse has blown somewhere.

–
Shawn X300 1995 Vanden Plas 4.0L
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –

6

In reply to a message from islandladd sent Thu 9 Dec 2010:

Not sure if this is of any help, but…

Firstly, according to the info I have here, the washer jet
heaters get a +12V feed from fuse #10 (5A) in the RH engine
fusebox and that comes via the ignition relay, so it’s only
on when the ignition key is at position 2.

Secondly, there’s a 13-pole white connector behind the RH
headlamps. It’s often (erroneously, in my view) called the
ECM connector and it is notorious for suffering corroded
contacts. On early cars it sits low down on a metal bracket
but later cars had it tied up higher to the wiring loom to
try and keep water out.

This connector carries all sorts of signals. Many of these
are to do with engine management and the engine can indeed
stop or falter if there’s corrosion there. However, one of
the non-engine signals it carries is from the temperature
sensor to the heated washer jets. It should be a red/slate
coloured wire but it’s not unheard of for the actual wire
colours to differ from what the circuit diagrams claim, so
be warned.

Thirdly, in the circuit between the white connector and the
sensor is another connector, which is a black 15-way one.
The red/slate wire enters this from the white connector and
changes to an orange/yellow wire on the final run to the
sensor. I believe that the black connector is in the front
RH wheel arch.

It may perhaps be worth your while checking the conditions
of these connectors if you haven’t already done so.

If you have access to the X300 CD-ROM, the wiring you want
to look at is on Fig 16.1 in the 1996 Electrical Guide, top
of the page. The +12V feed via the fuse is on Fig 01.4.

Connecting the red/slate wire from the heaters directly to
earth should cause them to heat up when the ignition key is
in position 2, irrespective of what the sensor is doing.

Hope this helps?

Cheers,
Gerald.–
The original message included these comments:

Checked the fuse in the right heal box for the heated jets and it
was fine. I was never aware that they operated any other way than
off the sensor. I think the X300 book says they operate at
temps<24 C Wish I could find a way to power them up. Seems like
it would be alot easier than trying to find that sensor
somewhere… I tried joining at the sensor connector just
figuring that the sensor basically just completes a circuit at a
certain temp turning on the jet heaters. I guess not, or I’m
missing something.

–
1996 X300 4.0
Suffolk, England, United Kingdom
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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