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Stage 1 Fans not coming on with A/C

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7 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHStage 1 Fans not coming on with A/C

Reported or suspected cause

resistors

Reported cause

No successful repair reported for this finding.

1
Identified cause
0
Suspected cause
0
Reported fixes
Read evidence and context

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 report identifying a cause
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.

Reported cause · Original poster

Got them installed over the weekend and good news, they both now work in both stages so I presume it was the resistors that failed on the old fans.

Stage 1 Fans not coming on with A/C
Frequently discussed work

Check fuses and relays and based

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
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.

Performed · outcome unconfirmed · Original poster

I checked the fuses and relays and based on the comments in this forum I went ahead and ordered two new fans.

Stage 1 Fans not coming on with A/C
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Leading evidence: 'resistors' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'resistors' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check fuses and relays and based' (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.

Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.

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1 matching discussions · 7 captured posts examined · 0 partial discussions

Compare 4 other evidence results

Check fuses and relays and based

Performed · outcome unconfirmed

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

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 performed work without a confirmed outcome
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.

Performed · outcome unconfirmed · Original poster

I checked the fuses and relays and based on the comments in this forum I went ahead and ordered two new fans.

Stage 1 Fans not coming on with A/C

Replace fans

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

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

Agree with replacing the fans, because, well, they are already 20 years old.

Stage 1 Fans not coming on with A/C

Replace resistors

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

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 · Original poster

I considered just changing the resistors but didn't trust my soldering skills under the car with the winter driving conditions - salt, slush etc.

Stage 1 Fans not coming on with A/C

Run tonight

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

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 · Original poster

I was able to take it out for a nice run tonight to warm up the engine even though it was only 30 F outside.

Stage 1 Fans not coming on with A/C
Frequently discussed actions (6)

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

Check fuses and relays and based

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that performed work without a confirmed outcome
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.

Performed · outcome unconfirmed · Original poster

I checked the fuses and relays and based on the comments in this forum I went ahead and ordered two new fans.

Stage 1 Fans not coming on with A/C

Replace fans

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

Agree with replacing the fans, because, well, they are already 20 years old.

Stage 1 Fans not coming on with A/C

Replace resistors

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 · Original poster

I considered just changing the resistors but didn't trust my soldering skills under the car with the winter driving conditions - salt, slush etc.

Stage 1 Fans not coming on with A/C

Run tonight

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 · Original poster

I was able to take it out for a nice run tonight to warm up the engine even though it was only 30 F outside.

Stage 1 Fans not coming on with A/C

Test activations

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 · Original poster

2001 C2 with 90K miles: while testing activations on my Durametric, I was surprised to discover that both rad fans were not working on stage 1 and only the right one in stage 2.

Stage 1 Fans not coming on with A/C

Use ac system

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

In fact the defroster will use the AC system to help remove moisture from the cabin, even if it is cold outside.

Stage 1 Fans not coming on with A/C
Reported and suspected causes (1)

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

resistors

No successful repair reported for this finding.

1
Identified cause
0
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that report identifying a cause
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.

Reported cause · Original poster

Got them installed over the weekend and good news, they both now work in both stages so I presume it was the resistors that failed on the old fans.

Stage 1 Fans not coming on with A/C
Coverage and how to read this overview

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.

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

  • Rennlist: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

0 acknowledgements have no verified action link; they do not establish a repair result.

Generation: 20261026T161109Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

2001 C2 with 90K miles: while testing activations on my Durametric, I was surprised to discover that both rad fans were not working on stage 1 and only the right one in stage 2. I checked the fuses and relays and based on the comments in this forum I went ahead and ordered two new fans. Got them installed over the weekend and good news, they both now work in both stages so I presume it was the resistors that failed on the old fans. My issue is that they did not come on stage 1 as expected when I turned on the a/c. My question is: is there a minimum ambient or engine temp that also affects fan operation with the a/c turned on? The ambient temp was approx 40 degrees F and I was just moving the car in the garage so engine was not up to temp. Thanks!

POST 2Original post

No minimum temp. Why did u get new fans? The replacement resistor from amazon is $10. A shop would be less then a hour to fix or do yourself. Pic of new and old resistors

POST 3 / ORIGINAL POSTEROriginal post

Quotes source post: 17206004

I considered just changing the resistors but didn't trust my soldering skills under the car with the winter driving conditions - salt, slush etc. up here. Removing them to solder on the bench was an option, but they were not too expensive on RockAuto (less than $100 each for Uro ones) and the old ones were original to the car with some corrosion so I thought it was better to replace.

POST 4Original post

Well, you got all the right stuff done and apparently the fans are now working on both stages. So that leaves...why do the fans not come on stage 1 when you put the AC on. Like he said, no minimum temperature. In fact the defroster will use the AC system to help remove moisture from the cabin, even if it is cold outside. Perhaps a little more testing. Put HVAC on lowest setting, then hit the AC button and see if the fans come on. Second, put the windshield defroster on, turn everything up to the highest temperature (warm/hot) and open the engine lid and see if the AC compressor is engaged (spinning). Actually you should do this in both scenarios to ensure the AC compressor is engaged.

POST 5Original post

Agree with replacing the fans, because, well, they are already 20 years old. But yeah, the resistors were the fault. No minimum temp for stage 1 as indicated by De Jeeper.

POST 6Original post

I sometimes forget how nice a heated garage with a lift. Not a bad price for the fans, cheaper then the factory resistor.

POST 7 / ORIGINAL POSTEROriginal post

Quotes source post: 17206223

I was able to take it out for a nice run tonight to warm up the engine even though it was only 30 F outside. Roads were dry and empty so I put on about 30 highway miles. So I had the defroster on with the a/c and when I got home the fans were on, working fine. Engine was at 180F and the fans stopped when I turned the a/c off. Came back on with the a/c so all is well. Thanks for the help!

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