atrioss

i'm pretty sure i have an elec prob with my honda... the speedometer quit working and the lights pulse when turned on at night. also, the fan motor for the a/c pulses when turned on as well. the alternator still seems to be charging the battery though, which is a relief.

at night when the lights are on, the engine rpm's will pulse at idle, but only if the a/c fan is blowing as well(just fan, no a/c compressor).

here's the dilemma... i went out and bought a diag code reader at autozone but the damn connector on the reader doesn't match the big fat green connector that's coming from the firewall to the ecu. there are some other cables running directly into the ecu, but those don't match either.

i've read some other threads here and at other sites... it seems like there is conflicting info about the service connector that you can jump with a paper clip or whatever... i thought that was only avail on pre-96 civics? i looked all around my ecu and can't find one...

what kind of readers do you all suggest for my ecu that are CHEAP and avail at a parts store?

Ef6-97

I got one at Farm N Fleet i dont remember what its called but i got it for 65 bucks.. i comes with a program for your computer where u just remember or write down the codes the code reader sends out.. and enter it in to your computer and it will tell you what codes its throwing and hopefully direct you to whre your problemed areas are! its orange lol thats all i remember and its not very big its about the size of an old electronic poker game lol

atrioss

OK i was thinking that i needed to connect the meter to a cable from the ecm... then i found out about the data port on the driver's side... the meter i bought works just fine now... i was just being a little lazy earlier, sorry about that..

anyway, it threw one code...... P1298 Electric Load Detector (ELD) Circuit High Voltage.... i read somewhere else that this is probably due to a bad ground/short. if i find a bad wire/connection, i'll fix it... and then check for a bad fuse.

carta79

You didn't know the difference between the data link connector and the service check connector. :chuckles:


If I were you I'd reset the ECM, start the engine and turn on the headlights. If DTC P1298 isn't indicated then it was just an intermittent failure. If the check engine light returns, disconnect the ELD 3P connector, turn the ignition to ON (II) and measure voltage between the body ground and the ELD 3P connector terminal 1. There also could be an open in the wire between No.15 Alternator SP sensor (7.5 A) fuse in the under-dash fuse/relay box and ELD.

I just threw a PO420 for catalyst efficiency yesterday after using sea foam. I reset the ECM and it didn't return. Also, I have never needed a diagnostic code reader, waste of money in my opinion.

atrioss

yep, i'm a auto-computer noob alright... i'm used to the pre-computer cars, lol... i drove and '03 jeep for a while but it was so new i never worked with it... i sold that gas-guzzler right before gas prices shot up earlier this year(just lucky i did that), and bought this civic.

i can't say i disagree with you on this. the only wiring prob i've noticed is that the neg battery terminal wire has some melted shielding about 4 inches from the post. the cable is very stiff and could not have possibly contacted the chassy, although it's been humid enough here lately-- it could possibly have arched from the open wire to the chassy or underside of the hood.

the other interesting thing about this is that over the last few days when i get out of the car and touch the door, i get a little shock. this never happened before this whole issue started.

the alternator fuse under the dash is good as well as a number of other fuses i checked. i think i'll just try resetting the ecm like you said.

carta79

I get shocked everytime I touch my door handle, it's a pretty strong shock to. It's quite strange because I've made every member of my family grasp the door handle and they never get shocked.

atrioss

I find out today that alternator is not charging the battery... it's just that the battery has been weakening very very slowly.. it doesn't start the car with as much power as before..

anyway the car is throwing p1298 code, which is electrical load detector high voltage... i assume that this high voltage is coming from the alternator... anyway, i'm afraid to replace the ELD for fear that the alt might blow it out again...

anyway, do you all think i should replace the alt first?

another question.... the battery light doesn't come on anymore when starting the car... does that mean i should replace the alt.... if the light is defective, will it affect the operation of the alt or charging system??


thanks for your input.

cfguy

I have been chasing this exact problem on a 97 civic. Here's what I've done to date:

Problem: Alternator is not charging upon start up and at idle. Once engine RPM are increased above 2400 (in park/can not moving) the number 15 fuse in the under dash panel blows and the alternator charges erratically, rapidly alternating between 0 – above 19 volts.

Here are the steps we’ve taken to try and resolve the issue:

- Replaced alternator twice
- Replaced battery
- Cleaned all visible grounds
- Removed all non-essential fuses from both the under dash and engine - compartment and ran engine. Results were the same.
- Completely removed gauge cluster from the dash to eliminate a potential tach/guage short.
-Removed and inspected engine compartment fuse box. Inspected ELD and plugs in box.
-Inspected visible wires under hood and under dash for indications of shorts or breaks

We have checked ohms on a few fires and here are the results:
- Black and white wire side of number 15 fuse shorted to ground (key in off position)
-White and blue wire running to alternator (checked by unplugging harness from alternator) shorted to ground (key in off position)
-Unplugged harness from VSS and check each wire with the following results
o Black/Yellow 2M ohms
o Black 0 ohms
o Blue/White 1.8M ohms

Any ideas where we should go next?

Thanks!

dan peterson

I have had the same problem with the speedo bouncing and the lights pulsing on my 97 civic. It only does it when you give it gas and does not do it at idle, check engine light came on at the same time everything else started. Any suggestions as to what I should start with first for fixing. 1997 honda civic 183,000, one owner car

dan peterson

forgot to mention that the car had a new alternator 1 year ago and the battery is 3-4 years old