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Hi Everybody
I am new to this forum. and looking for valuable assistance,
Have following vehicle XJ/300 1996 4.0l
Turn on igniton and all dash lights up sides come on for few seconds then go of (see pics)
Red P comes on gear shifter, (cannot take out of park with ignition on and foot on brake ?)
The radiator cooling fan come on full speed
turn key to position 3
Car wont crank
Have checked all fuses are ok locations 2x engine bay 2x heal board 1x boot
relays are clicking as they are powered up
checked inertia switch and functions ok and confirmed reset
First thing I notice other than the bulb failure warning on the left is that the Check Engine light is NOT lit. The engine will not crank if the CEL is not lit.
The instrument cluster is supposed to send the "Check Engine" signal to the Body Processor Module, which then enables cranking.
The problem could lie within the cluster or the BPM. There are other possibilities too.
The transmission should be able to come out of Park when the ignition is on and foot is on brake. This leads me to think that the brake light switch is not working. That is located on the brake pedal lever and activates the shifter unlock mechanism. Check the brake lights.
Lastly for now, the engine fans will normally run all the time, on low speed.
The "Check Engine" light needs to stay on when the other lights go off. Without the Check Engine light the BPM (Body Processor Module) will not enable cranking.
The reason for this is usually that the car is immobilised. Do you have another key to try? Are you using the original keys?
I'm assuming this is not a US model (which doesn't have an immobiliser). I think all other regions do have it.
While @SleekJag12 was typing his reply I was typing this in your other post.
The "Check Engine" light needs to stay on when the other lights go off. Without the Check Engine light the BPM (Body Processor Module) will not enable cranking.
The reason for this is usually that the car is immobilised. Do you have another key to try? Are you using the original keys?
I'm assuming this is not a US model (which doesn't have an immobiliser). I think all other regions do have it.
Your key should have a raised bump micro chip in it
In the trunk there is a large panel on the fwd wall that comes out
Above the fuel tank you will find a large connector with a lock over bar on it that should be tywraped to keep it from migrating unlocked and a loose connection
Without disturbing it what do you see if the lockbar is tywrapped
Last edited by Parker 2; Jul 25, 2020 at 07:40 AM.
Hi sorry if this is double post as tried to send earlier but cannot see it online ?
I have checked the car and found below for connector it has tie clip on cables but not on lock mechanism
Checked the key and it has original Jag key
Brake lights come on when press brake pedal so switch must be working (but not come out of park)
have no headlights only side lights
no direction indicators or hazard warning lights
No windscreen wiper function
The lock bar on the BT4 connector looks to be in the lock position so we'll leave it alone for now as it can be very hard to get on and you can break it
The BPM has lots of failure modes. It controls (or is involved with) many functions. Sometimes just one function will fail, sometimes multiple functions.
I'm not aware of anyone ever repairing a BPM. In the UK, used units can be bought for around Ł20.
You can try and diagnose the BPM a bit more by testing inputs and outputs. Attached is a spreadsheet I made some time ago that consolidates the data from the Electrical Guide. That might help a bit.
The BPM has a role to play in all the functions that are not working on your car, so it's a prime candidate.
Hi
I have received and fitted body module and now have all functions working but car still not starting as check engine light not staying on,
could anybody recommend good scanner tester for this model with key programming function, Also to program the keys would I need two keys or just the one or anybody know an immobiliser bypass as very difficult to get dealer to help here in India
XJ / X300 1996. 4.0l
