i found the answer that i was looking for:
here is a recommended test for that also, that can be done with a multi meter. It is from a service bulletin and it gives the current amounts that are allowable.
Also a bulltin on a bypass harness for the general electric control module. Let me give you them both.
Battery - Quiescent Drain Current - Specifications
Remove and destroy Bulletin S414-01, dated 6/99. Replace with this Bulletin. The entire test procedure has been revised.
This bulletin provides specifications for quiescent current drains from the vehicle battery, as well as a procedure for measuring them using a digital volt/ohmmeter (DVOM).
CHECKING QUIESCENT DRAIN CURRENT
Note: The four (4) Switched Power Relays in the Rear Distribution Box will stay active until the last SCP message is sent. This process will last up to 30-40 minutes. Opening any of the doors or the trunk during the Quiescent Drain Test will cause the timer to reset and delay the shut down of the relays. It is also recommended that the battery isolation device remain attached to the battery and NOT be removed until the vehicle is ready for delivery to the retail customer. This will prevent unnecessary drain of the battery and inconvenience to the customer.
Record the following system settings prior to disconnecting the battery so that they may be reset to the customers preferred setting.
^ Clock time setting
^ Clock 12/24 hour setting
^ CD compress mode (if equipped. Radio must be in CD mode to check this setting.)
^ Navigation volume defaults to 14 (if equipped)
^ Voice feedback volume defaults to 14 (if equipped - voice training is not lost).
^ Gear box mode
^ Radio presets AM/FM
^ Compass calibration and zone setting
^ Navigation memory will be retained if the battery has not been disconnected longer than 24 hrs.
The trip computers (both A & B) will reset to zero, these however cannot be returned to prior readings.
Use a DVOM as follows to measure quiescent drain current:
1. Disconnect the battery negative cable and check the battery off-load voltage. If the voltage is below 12.5 volts, recharge the battery and retest the voltage. If OK, reconnect the negative cable.
2. Rotate the ignition switch to position II and leave for 30 seconds, then turn the ignition off and remove the key.
3. Ensure that the exterior light switch is turned off, the radio is switched off, the mobile phone (if equipped) is also turned off. Ensure that the interior light switches are turned off.
4. Close all the doors, and the hood. With the trunk open, move the latch to the closed position. Disconnect the trunk lights.
5. Disconnect battery negative cable. Connect a DVOM between the negative cable and battery to perform the test. The vehicle's alarm system and radio will default to active when the battery is reconnected. Press the key-fob transmitter to disarm the alarm. Turn the radio off.
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6. Measure the quiescent current drain. The expected readings are as shown.
Note: All the above figures are approximate and can vary from vehicle to vehicle.
However, after 45 minutes the quiescent drain of any vehicle equipped with Jaguar-approved accessories should be no greater than 30 milliamps.
If the test is carried out with the security system in its armed state, the drain should be approximately the same as the readings above, but there will be a pulse to 46 milliamps for 0.25 second when the LED flashes.
Always ensure that a 'clean' connection is made when connecting the battery. If a temporary contact is made, disconnect, wait 60 seconds, then reconnect cleanly
General Electronic Control Module - Battery Feed Problem
High Quiescent Drain - Intermittent Loss of Permanent Power Feed - Install Forward Harness Bypass Lead
Some 2000 MY S-TYPE vehicles may experience an intermittent loss of permanent battery power feed from the primary junction box to the General Electronic Control Module (GECM). The vehicle may experience the following symptoms:
^ The headlights may flash once on their own, this has also been reported to happen at a specific time after the ignition has been turned off (30 minutes or 60 minutes).
^ There would also be a higher than normal battery quiescent drain, due to the four ignition power relays (located in the luggage compartment) being re-energized at the 30 or 60 minutes mark.
In case of a customer complaint of the above symptoms on a 2000 MY S-TYPE within the above VIN range, check the power feed at the GECM and the continuity of the wire from the GECM to the primary junction box.
1. Turn the ignition to off.
2. Using a DVOM, set to voltage.
3. Probe the back of pin 6 (orange and green wire) at connector FH59 on the GECM. Refer to the S-TYPE 2000 MY Electrical Guide, Fig. 01.5.
4. Reading should remain at battery voltage and monitor for any voltage change for approximately 10 minutes.
5. If the voltage is considerably lower than the battery voltage, refer to the procedure for installing the forward harness bypass lead. If the voltage remains constant at battery voltage, refer to the resistance check
1. Set the DVOM to read resistance. Touch the two leads to each other and zero the meter or note the resistance of the leads.
2. Disconnect FH59 from the GECM.
3. Disconnect FH7 from the primary junction box. Refer to the S-TYPE 2000 MY Electrical Guide, Fig. 01.2.
4. Connect one DVOM lead to pin 6 at connector FH59 and the other to pin 2 (orange and yellow wire) at connector FH7. (Gray 6 way connector located uppermost of the primary junction box in the central position)
5. Check the resistance reading for continuity Resistance should be less than 1 ohm.
6. If the reading shows a high resistance, refer to the procedure for installing the forward harness bypass lead.
INSTALLING THE FORWARD HARNESS BYPASS LEAD.
If the above checks show low voltage or high resistance, install a bypass lead to take the permanent power feed to the GECM away from the forward harness as follows:
Record the following customer settings before disconnecting the battery so they can be reset to the customer's preferred setting:
^ Clock 12/24 hr setting
^ CD compress mode (if equipped)
^ Navigation volume defaults to 14 (if equipped)
^ Voice feedback volume defaults to 14 (if equipped)
^ Transmission mode (sport/normal)
^ Radio presets - AM/FM, Bass, Treble settings
^ Compass calibrations and zone setting
Navigation memory will be retained if the battery is not disconnected longer than 24 hours.
Always reset the clock to the correct time before returning the vehicle to the customer.
1. Disconnect the car battery (Refer to workshop manual JTIS CD ROM section 414-01, SRO 86.15.01)
2. Remove both of the plastic A-post side trims. (Refer to workshop manual (JTIS CD ROM) section 501-05, SRO 76.13.31)
3. Disconnect connector FH59 from the GECM.
4. Disconnect the connector FH7 from the primary junction box.
5. Connect the relevant ends of the bypass lead to the primary junction box and the disconnected harness connector.
6. Pull the interior carpets away from the firewall and both footwells.
7. Route the bypass lead from the primary junction box, around the foot well to the console, taping at intervals to the firewall.
8. Route the bypass lead through the opening at the front edge of the air conditioning (A/C) assembly across to the other side.
9. Position the bypass leads inline connector within the A/C aperture.
Note: When positioning the bypass lead inline connector within the A/C aperture, ensure it will not rattle when the vehicle is moving.
10. Route the bypass lead across the foot well towards the left A-post, taping at intervals to the firewall.
11. Using an appropriate terminal removal tool, remove pin 6 from connector FH59.
Note: The pin to be removed has an orange and green wire color.
12. Cut-off the terminal and insulate using a termination splice and heatshrink tubing, and tape the lead to the harness.
Note: The heatshrink tubing and termination splice are available from the harness repair kit.
13. Insert the terminal from the bypass lead into the redundant aperture.
14. Secure any excess bypass lead, ensuring that it will not create any future rattles.
15. Reconnect connector FH59 to the GECM.
16. Refit all the interior trim.
17. Reconnect the car battery. (Refer to workshop manual JTIS CD ROM section 414-01 SRO 86.15.01). Reset the customer's preferred settings as noted at the beginning of this procedure.
18. Check the operation of the vehicle.
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Expert: Super mechanic
Pos. Feedback: 98.5 %
Answered: February 5 2009
ASE master, 30 years
Posted 185 days and 10 hours ago.
I don't know if this will solve the problem or not, but your help is worth more than the $15.00
I wish the local Jag mechanics would put as much effort into the solution.
Posted by Super mechanic 185 days and 8 hours ago.
Your welcome and come again. Thank you and best wishes on it.
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