Battery Cable Disconnection Process/NAV Computer Memory Corruption (86/05/01/NAS)

Publication date: 2001-03-23
Reference number: 86/05/01/NAS

BATTERY CABLE DISCONNECTION PROCESS/NAV COMPUTER MEMORY CORRUPTION

TECHNICAL SERVICE BULLETIN

Reference Number(s): 86/05/01/NAS, Date of Issue: March 23, 2001

LAND ROVER:	Range Rover (LP)
ISSUE:	1
SECTION:	Electrical
AFFECTED VEHICLES:	Range Rover (LP) All vehicles with NAV System

SITUATION:

BLANK SCREEN AND INOPERATIVE RADIO VOLUME

Loss of radio volume control, a blank navigation system screen, or a NAV power LED which fails to light may be experienced after work has been performed on a vehicle that required disconnection of the negative battery cable. Similar symptoms may be present if a vehicle with NAV has been jump started or had a battery charger applied under certain conditions.

RESOLUTION:

WAIT FOR NAV SYSTEM TO POWER DOWN BEFORE ALTERING POWER SOURCE

The NAV computer performs a brief five-second write-to-memory function 55 seconds after the ignition is switched off. When this function is completed the LED will extinguish. It is only AFTER this function has been completed that any change to the battery connections can be made. Ensure that the procedures and precautions in the bulletin are always observed.

PARTS INFORMATION:

PARTS INFORMATION

P/N	Description
YIB000110	NAV Computer

WARRANTY CLAIMS:

Information Only

Normal warranty policy and procedures apply

REPAIR PROCEDURE

PROBLEM VERIFICATION

NOTE: Blank screens and the other navigation problems may have alternate causes.

Verify that the white connector behind the NAV display is completely mated.
Inspect wires at connector to determine if any is damaged.
Verify that map CD 2000.2 or later is in use. Earlier CD's can give these symptoms.
If steps 1 through 3 do not resolve the display and volume problems, wait more than one minute for the NAV computer LED to extinguish.
Install a known good NAV computer to verify that the problem is the computer itself.
If indicated by testing, replace damaged NAV computer with new component.

POWER INTERRUPTION PRECAUTIONS

CAUTION: Always ensure that power interruption takes place only after the NAV power indicator LED has extinguished - at least 1 minute after turning ignition to the OFF position. Failure to follow this precaution could result in destruction of the NAV computer memory, rendering the computer inoperative.

CAUTION: As per the owners' manual and the workshop manual, never charge the battery in the vehicle. Always remove battery cables and remove battery from vehicle prior to recharging.

Remove battery cables using the following procedures:
- Turn vehicle ignition to the OFF position.
- Wait until NAV power LED extinguishes after one minute.
- Remove negative battery cable.
- Remove positive battery cable if required.
Apply jumper cables for a discharged battery using the following procedures:
- Verify that the ignition switch has been turned to the OFF position for more than 1 minute.
- Connect positive jumper cable.
- Connect negative jumper cable.
- Start the vehicle.
- Disconnect negative jumper cables from the battery.
- Disconnect positive jumper cable.