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Resetting ECU?

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4 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

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YOUR RESEARCHResetting ECU?

Leading reported evidence

Disconnect battery

Suggestion or failed attempt

No successful repair reported for this finding.

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Reported fixes: 0
Unsuccessful attempts: 1
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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
A 99 C2 has Motronic version 5.2.2 and the easiest way is to disconnect the battery for about a minute.
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Resetting ECU?

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Leading evidence: 'Disconnect battery' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Disconnect battery' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

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1 matching discussions · 4 captured posts examined · 0 partial discussions

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Disconnect negative terminal of the battery

Suggestion or failed attempt

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Discussions that contain suggestions: 1

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Suggestion
Leave the key in this position, and disconnect the negative terminal of the battery for a minute.
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Resetting ECU?

Reset by putting the turning the key

Suggestion or failed attempt

No successful repair reported for this finding.

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Reported fixes: 0
Unsuccessful attempts: 1
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Discussions that contain suggestions: 1

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Suggestion
On the later cars, those with Fly-by-wire throttle you can also do a throttle body reset by putting the turning the key to the position when all the lights are on on the dash and leaving it for 30+ secs, you might be able to hear a few clicks etc from the engine bay.
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Resetting ECU?

Frequently discussed actions (3)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Disconnect battery

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
A 99 C2 has Motronic version 5.2.2 and the easiest way is to disconnect the battery for about a minute.
Original post Read captured discussion
Resetting ECU?

Disconnect negative terminal of the battery

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
Leave the key in this position, and disconnect the negative terminal of the battery for a minute.
Original post Read captured discussion
Resetting ECU?

Reset by putting the turning the key

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

Discussions that contain suggestions: 1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion
On the later cars, those with Fly-by-wire throttle you can also do a throttle body reset by putting the turning the key to the position when all the lights are on on the dash and leaving it for 30+ secs, you might be able to hear a few clicks etc from the engine bay.
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Resetting ECU?

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Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

4 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

911uk: 1 discussions

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Generation: 20261027T044418Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Apologies if this has been covered many times before, I have searched but cannot find a full answer... Since fitting my CAI I have a slight flatspot at 5,200 rpm and I figured that a ECU reset was probably worth a go. What is the best process for doing this on a 99 C2 Cab?

POST 2Original post

A 99 C2 has Motronic version 5.2.2 and the easiest way is to disconnect the battery for about a minute. Switch on the ignition, but don't start the car. Leave the key in this position, and disconnect the negative terminal of the battery for a minute. This procedure will stop the alarm going off when you disconnect. For later cars see: http://911uk.com/viewtopic.php?t=41260&postdays=0&postorder=asc&start=7

POST 3 / ORIGINAL POSTEROriginal post

Thank you Richard, much appreciated. Will give it a whirl tomorrow :thumbs:

POST 4Original post

On the later cars, those with Fly-by-wire throttle you can also do a throttle body reset by putting the turning the key to the position when all the lights are on on the dash and leaving it for 30+ secs, you might be able to hear a few clicks etc from the engine bay.

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