Range Rover P38 SRS ECU

Hi - My 2001 2.5 p38 has the SRS light on. After following numerous pieces of advice I was going to replace the SRS ECU. There appears to be two types - one for a single point system - and one for a distributed system. As I cannot find any front crash sensors I assume mine is a single point system. The two ECUs I have found on Ebay are AMR4709 and AWR6507 but I don't know which one is for single or distributed systems. I don't was to dismantle my centre console yet to find the one installed until I'm ready withe a replacement. Any advice welcome

what have you done so far to decide there is an ECU problem?

kermit_rr said:

what have you done so far to decide there is an ECU problem?

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As above ^^^^^. A duff bulb, there are 2 in the dash, will cause the remaining bulb to stay on.
Most common problem is the yellow connector under the drivers seat coming loose.
The ECU's rarely fail.
You may need diagnostics to clear any fault condition.

Had a diagnostic check and it said there was a "Front impact sensor configuration fault". As there doesn't appear to be any front sensors, I assume I have the single sensor system which is part of the ECU. Again any advice is welcome.

I did check the bulbs and they are both ok.

Mozzaa said:

Had a diagnostic check and it said there was a "Front impact sensor configuration fault". As there doesn't appear to be any front sensors, I assume I have the single sensor system which is part of the ECU. Again any advice is welcome.

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The sensors are internal to the ECU. Normally, the only thing that can cause a front sensor fault is a frontal impact, the sensor is a very simple device which should not be expected to fail.
What diagnostics were used? The P38 is not OBD compliant and requires the correct diagnostic equipment.

An auto electrician used a MaxiDAS DS808

Mozzaa said:

An auto electrician used a MaxiDAS DS808

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I don't know that kit but it's possible the fault it recorded is not the actual fault.
Look under the drivers seat, there is a yellow connector, disconnect and reconnect it and see what you get.

Datatek said:

I don't know that kit but it's possible the fault it recorded is not the actual fault.
Look under the drivers seat, there is a yellow connector, disconnect and reconnect it and see what you get.

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A quick search gives me no confidence that the diagnostic tool will correctly define the fault codes, it seems to depend on the revision level.

Datatek said:

I don't know that kit but it's possible the fault it recorded is not the actual fault.
Look under the drivers seat, there is a yellow connector, disconnect and reconnect it and see what you get.

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You sure it's driver's seat, Keith?

Tenebreaux said:

You sure it's driver's seat, Keith?

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That's the one that gives the most trouble.

Datatek said:

That's the one that gives the most trouble.

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I bow to your superior knowledge. Just that I seem to remember it was the passenger side when I had to do mine.

Tenebreaux said:

I bow to your superior knowledge. Just that I seem to remember it was the passenger side when I had to do mine.

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The passenger side can also give trouble but the passenger seat tends to be moved and/or occupied less often than the drivers seat so gives less trouble.

I'll try both seats. Cheers.

All I can say guys is thank you. Disconnected both seat plugs and reconnected and hey presto no more SRS light.
I applaud your knowledge. Many thanks and hopefully many more carefree miles in my P38.

Mozzaa said:

All I can say guys is thank you. Disconnected both seat plugs and reconnected and hey presto no more SRS light.
I applaud your knowledge. Many thanks and hopefully many more carefree miles in my P38.

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Just goes to show, you cannot trust non specific diagnostics

These sensors?


Right on the front on early models so anyone nudges you in a car park etc can set it off. Later models they moved them back on the chassis leg somewhere there

RangeRoller dt said:

These sensors?

View attachment 267421
Right on the front on early models so anyone nudges you in a car park etc can set it off. Later models they moved them back on the chassis leg somewhere there

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There are only 2 SRS sensor positions that I know of, one on each of the front chassis legs as per your photo on early cars and internal to the ECU on later models. I don't know the change over date.
It would take a pretty hefty nudge in the car park to trigger the sensor, they are inertial devices.

Datatek said:

It would take a pretty hefty nudge in the car park to trigger the sensor, they are inertial devices.

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Don't want them going off when you're off road

kermit_rr said:

Don't want them going off when you're off road

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Absolutely