Hello,

Does the 3.0 S-type have an "ECT" Engine Coolant Temp Sensor or is it just the 4.0 V8?

Nothing on JTIS for 3.0 - just the "CHT" - Cylinder Head Temp.

Also my coolant tank is virtually empty - yet no warning lamp indication???

Can anyone help?

Regards,

 

Every car with OBD must report ECT so it's a puzzle!

 

Oh dear, not another puzzle.
Well the tank needs to come off then.

Nothing on JTIS either!

 

JEPC shows two different part numbers for the coolant sensor depending on VIN if I'm reading it correctly.

LRA1600AA
or
XR813484 To VIN (M45254)

 

Leonard_85 - I don't believe the ECT sensor would be located in the coolant expansion tank. The ECT sensor is located on the thermostat housing assembly. The sensor in the tank is related to the level of coolant and will flag a "low coolant" message on the dashboard.

 

The cylinder head temp sensor (XR813484) is located in bank 2 (left bank) and is a long brass colored device threaded into the head. I measures the cylinder head temp directly (NOT THE COOLANT)

bob gauff

 

Yep.... but the OP asked whether there is an ECT (on his engine year & kind).

It appears not... which doesn't sound right!

 

Thanks everyone,

I searched the electrical archives for 2000 3.0 ltr -

It would appear only the V8 models benefit from a "Level Sensor"...

This explains why after topping-up to fill-level and test driving the only apparent indicator was 1/2 ltr of coolant on my driveway from a leaking (and comedy squeaking) hose.

As for the "ECT" - JTIS Electrical states location as on elbow bend adjacent to tank???

Puzzled!

 

The coolant level sensor was deleted and a software upgrade to eliminate the 'LOW COOLANT' message from the missing component.

We did hundreds of cars and the newer replacement coolant reservoirs do not have the level sensor installed.

If anyone still has a working level sensor please note that if it becomes contaminated and blows the fuse, the gearbox will go into 'limp home' mode because that fuse also controls some of the gearbox functions. (It took us a little while to figure that one out.)

bob gauff

 

I think the OP was also (originally) asking about the ECT (on his era engine). Does it really not exist?

 

The 3.0 V6 has a cylinder head temp sensor and the V8 has a coolant temp sensor.

bob gauff

 

Hi Bob,

Thanks for your input.

It was the tank that was cracked in several places (and whistling away when hot).

You mentioned the level sensor fuse affects the gearbox behaviour - is this relevant to my vehicle - the 2000 3.0 V6? The leaking coolant has dripped onto connectors far beneath the brake booster behind front wheel..any relevance?

I'm still fishing around for possible electrical issues on my transmission.

XR816503 - engineering from another planet for another planet, clearly.

 

Bob,


"the gearbox will go into 'limp home' mode because that fuse also controls some of the gearbox functions" - This has dominated my car for the past 2 months - i'm praying for some good english weather so I can perform solenoid continuity tests.

However whilst you're here, could you point me to random components which may be knocking my transmission into limp/ restriction? Error is P0733.

Both my tie-rods are badly rotten at both ends - could the abs sense unnatural movement in rear-wheels under power (i.e incorrect ratio - p0733 - this would make a good write-up).

Muchos Gracias.

 

"On some 4.0L V8 S-TYPE vehicles within the above VIN range, coolant has entered the
coolant level sensor causing it to fail and give false readings. It has been decided that
the coolant level sensor should be disabled for those 4.0L V8 vehicles affected within
the above VIN range. The coolant level sensor was intended as a indication to the driver
in case the coolant level is too low, since these vehicles are not equipped with fail-safe
cooling as are the 3.0L V6 vehicles.
To disable the coolant level sensor follow the workshop procedure provided in this
bulletin."

The coolant level sensor IS NOT FITTED TO THE 3.0 ENGINE CAR

If the 3.0 overheats, the engine will try to inhibit cylinders, lower power etc.
If you don't shut it down the ECM will do that for you.

There is no level sensor connector.

I don't know of a common fault for the P0733.

Here is the DTC guide.

bob gauff

 

Bob,

We figured no level sensor when I pulled the tank off. It's the ECT subject which has gotten me worked-up.

"If the 3.0 overheats, the engine will try to inhibit cylinders, lower power etc.
If you don't shut it down the ECM will do that for you"

Are you suggesting the engine should misfire/ stutter if pressure is being lost on the tank?

Thanks,

 

Because the 3.0 has CHT it can take evasive action (if the engine overheats) by shutting down cylinders. It shouldn't misfire because it won't have put fuel in when it shuts a cylinder down. I expect you'd feel the engine running oddly. Maybe Bob has even more data...

Just losing coolant pressure shouldn't matter. It would need to lose coolant as well, I expect, to cause an overheat.

Goodness only knows (meaning Jaguar only knows!) how they report ECT via OBD since there isn't an ECT. Maybe CHT and perhaps subtract a few degrees!!

 

Driving 1999 S type over 215.000 Km. still runs well however I figured out that So called cylinder head temp sensor with white connector which located between the two ignition coils on the drivers cylinder head loosed and its tip broken (A glass type material,ceramic perhaps). I could not find the exact part number and no idea what it does. Need help. Thanks in advance